Nanomaterials

13 pages, 5241 KiB

Open AccessArticle

Bimetallic MOFs-Derived Hollow Carbon Spheres Assembled by Sheets for Sodium-Ion Batteries

by Hui Yang, Ang Li, Chunli Zhou, Xuewei Liu, Xiaohong Chen, Haiyan Liu, Tao Liu and Huaihe Song

Nanomaterials 2022, 12(21), 3926; https://doi.org/10.3390/nano12213926 - 07 Nov 2022

Viewed by 1564

Abstract

Metal-organic frameworks (MOFs) have attracted extensive attention as precursors for the preparation of carbon-based materials due to their highly controllable composition, structure, and pore size distribution. However, there are few reports of MOFs using p-phenylenediamine (pPD) as the organic ligand. In this work, [...] Read more.

Metal-organic frameworks (MOFs) have attracted extensive attention as precursors for the preparation of carbon-based materials due to their highly controllable composition, structure, and pore size distribution. However, there are few reports of MOFs using p-phenylenediamine (pPD) as the organic ligand. In this work, we report the preparation of a bimetallic MOF (CoCu-pPD) with pPD as the organic ligand, and its derived hollow carbon spheres (BMHCS). CoCu-pPD exhibits a hollow spherical structure assembled by nanosheets. BMHCS inherits the unique hollow spherical structure of CoCu-pPD, which also shows a large specific surface area and heteroatom doping. When using as the anode of sodium-ion batteries (SIBs), BMHCS exhibits excellent cycling stability (the capacity of 306 mA h g⁻¹ after 300 cycles at a current density of 1 A g⁻¹ and the capacity retention rate of 90%) and rate capability (the sodium storage capacity of 240 mA h g⁻¹ at 5 A g⁻¹). This work not only provides a strategy for the preparation of pPD-based bimetallic-MOFs, but also enhances the thermal stability of the pPD-based MOFs. In addition, this work also offers a new case for the morphology control of assembled carbon materials and has achieved excellent performance in the field of SIBs. Full article

(This article belongs to the Special Issue Carbon Nanomaterials for Electrochemical Energy Storage)

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10 pages, 1849 KiB

Open AccessArticle

Investigation of a Novel Injectable Chitosan Oligosaccharide—Bovine Hydroxyapatite Hybrid Dental Biocomposite for the Purposes of Conservative Pulp Therapy

by Mingkai Cai, Jithendra Ratnayake, Peter Cathro, Maree Gould and Azam Ali

Nanomaterials 2022, 12(21), 3925; https://doi.org/10.3390/nano12213925 - 07 Nov 2022

Cited by 2 | Viewed by 1316

Abstract

This study aimed to develop injectable chitosan oligosaccharide (COS) and bovine hydroxyapatite (BHA) hybrid biocomposites, and characterise their physiochemical properties for use as a dental pulp-capping material. The COS powder was prepared from chitosan through hydrolytic reactions and then dissolved in 0.2% acetic [...] Read more.

This study aimed to develop injectable chitosan oligosaccharide (COS) and bovine hydroxyapatite (BHA) hybrid biocomposites, and characterise their physiochemical properties for use as a dental pulp-capping material. The COS powder was prepared from chitosan through hydrolytic reactions and then dissolved in 0.2% acetic acid to create a solution. BHA was obtained from waste bovine bone and milled to form a powder. The BHA powder was incorporated with the COS solution at different proportions to create the COS–BHA hybrid biocomposite. Zirconium oxide (ZrO₂) powder was included in the blend as a radiopacifier. The composite was characterised to evaluate its physiochemical properties, radiopacity, setting time, solubility, and pH. Fourier-transform infrared spectroscopic analysis of the COS–BHA biocomposite shows the characteristic peaks of COS and hydroxyapatite. Compositional analysis via ICP-MS and SEM-EDX shows the predominant elements present to be the constituents of COS, BHA, and ZrO₂. The hybrid biocomposite demonstrated an average setting time of 1 h and 10 min and a pH value of 10. The biocomposite demonstrated solubility when placed in a physiological solution. Radiographically, the set hybrid biocomposite appears to be more radiopaque than the commercial mineral trioxide aggregate (MTA). The developed COS-BHA hybrid biocomposite demonstrated good potential as a pulp-capping agent exhibiting high pH, with a greater radiopacity and reduced setting time compared to MTA. Solubility of the biocomposite may be addressed in future studies with the incorporation of a cross-linking agent. However, further in vitro and in vivo studies are necessary to evaluate its clinical feasibility. Full article

(This article belongs to the Special Issue Advancements of Nanomaterials in Oral Health and Clinical Dentistry)

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13 pages, 5512 KiB

Open AccessArticle

Optical Properties of Ag Nanoparticle Arrays: Near-Field Enhancement and Photo-Thermal Temperature Distribution

by Daobin Luo, Pengcheng Hong, Chao Wu, Shengbo Wu and Xiaojing Liu

Nanomaterials 2022, 12(21), 3924; https://doi.org/10.3390/nano12213924 - 07 Nov 2022

Cited by 2 | Viewed by 1426

Abstract

The near-field and photo-thermal properties of nanostructures have always been the focus of attention due to their wide applications in nanomaterials. In this work, we numerically investigate the near-field and photo-thermal temperature distribution in a nanoparticle array when the scattering light field among [...] Read more.

The near-field and photo-thermal properties of nanostructures have always been the focus of attention due to their wide applications in nanomaterials. In this work, we numerically investigate the near-field and photo-thermal temperature distribution in a nanoparticle array when the scattering light field among particles is considered. ‘Hot spots’, which represent strong electric field enhancement, were analyzed at the difference of the particle size, particle spacing and the polarization direction of the incident light. Interestingly, it is found that the position of the ‘hot spots’ does not rotate with the polarization direction of the incident light and always remains in the particle gaps along the line between particle centers. Moreover, the near-field is independent of the polarization in some special areas, and the factor of near-field enhancement keeps constant in these spots when the illumination polarization varies. As for photo-induced heating, our results show that both the temperature of the structure center and maximum temperature increase linearly with the particle number of the array while decreasing with the increase in particle spacing. This work provides some theoretical considerations for the near-field manipulation and photo-thermal applications of nanoarrays. Full article

(This article belongs to the Special Issue Plasmon Assisted Near-Field Manipulation and Photocatalysis)

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13 pages, 42223 KiB

Open AccessArticle

Surfactant-Modified CdS/CdCO₃ Composite Photocatalyst Morphology Enhances Visible-Light-Driven Cr(VI) Reduction Performance

by Wen-Yi Wang, Tian Sang, Yan Zhong, Chao-Hao Hu, Dian-Hui Wang, Jun-Chen Ye, Ni-Ni Wei and Hao Liu

Nanomaterials 2022, 12(21), 3923; https://doi.org/10.3390/nano12213923 - 07 Nov 2022

Cited by 1 | Viewed by 1382

Abstract

The surfactant modification of catalyst morphology is considered as an effective method to improve photocatalytic performance. In this work, the visible-light-driven composite photocatalyst was obtained by growing CdS nanoparticles in the cubic crystal structure of CdCO₃, which, after surfactant modification, led [...] Read more.

The surfactant modification of catalyst morphology is considered as an effective method to improve photocatalytic performance. In this work, the visible-light-driven composite photocatalyst was obtained by growing CdS nanoparticles in the cubic crystal structure of CdCO₃, which, after surfactant modification, led to the formation of CdCO₃ elliptical spheres. This reasonable composite-structure-modification design effectively increased the specific surface area, fully exposing the catalytic-activity check point. Cd²⁺ from CdCO₃ can enter the CdS crystal structure to generate lattice distortion and form hole traps, which productively promoted the separation and transfer of CdS photogenerated electron-hole pairs. The prepared 5-CdS/CdCO₃@SDS exhibited excellent Cr(VI) photocatalytic activity with a reduction efficiency of 86.9% within 30 min, and the reduction rate was 0.0675 min⁻¹, which was 15.57 and 14.46 times that of CdS and CdCO₃, respectively. Finally, the main active substances during the reduction process, the photogenerated charge transfer pathways related to heterojunctions and the catalytic mechanism were proposed and analyzed. Full article

(This article belongs to the Special Issue Nanoscale Materials for Water Purification and Catalysis)

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25 pages, 6093 KiB

Open AccessArticle

Surface-Oxidised Carbon Nanofibre-Based Nanofluids: Structural, Morphological, Stability and Thermal Properties

by Norshafiqah Mohd Saidi, Norli Abdullah, Mohd Nurazzi Norizan, Nurjahirah Janudin, Noor Azilah Mohd Kasim, Mohd Junaedy Osman, Imran Syakir Mohamad and Mohd Afzanizam Mohd Rosli

Nanomaterials 2022, 12(21), 3922; https://doi.org/10.3390/nano12213922 - 07 Nov 2022

Cited by 2 | Viewed by 1774

Abstract

The reputation of nanofluids as a convenient heat transfer media has grown in recent years. The synthesis of nanofluids is often challenging, particularly carbon-based nanofluids, due to the rapid agglomeration of the nanoparticles and the instability of the nanofluids. In this regard, surface [...] Read more.

The reputation of nanofluids as a convenient heat transfer media has grown in recent years. The synthesis of nanofluids is often challenging, particularly carbon-based nanofluids, due to the rapid agglomeration of the nanoparticles and the instability of the nanofluids. In this regard, surface modification and surfactant addition are potential approaches to improve the physical and thermal properties of carbon-based nanofluids that have been studied and the structural, morphological, and thermal characteristics of surface-oxidised carbon nanofibre (CNF)-based nanofluids has been characterised. Commercial CNF was first subjected to three different acid treatments to introduce surface oxygen functional groups on the CNF surface. Following the physical and thermal characterisation of the three surface-oxidised CNFs (CNF-MA, CNF-MB, and CNF-MC), including Raman spectroscopy, Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM), the CNF-MB was selected as the best method to synthesise the surface-oxidised CNF-based nanofluid. A total of 40 mL of ultrapure water was used as a pure base fluid and mixed with the surface-oxidised CNF at a concentration range of 0.1–1.0 wt.%, with a fixed of 10 wt.% amount of polyvinylpyrrolidone (PVP). The thermal conductivity of CNF-based nanofluid was then characterised at different temperatures (6, 25, and 40 °C). Based on the results, surface oxidation via Method B significantly affected the extent of surface defects and effectively enhanced the group functionality on the CNF surface. Aside from the partially defective and rough surface of CNF-MB surfaces from the FESEM analysis, the presence of surface oxygen functional groups on the CNF wall was confirmed via the Raman analysis, TGA curve, and FTIR analysis. The visual sedimentation observation also showed that the surface-oxidised CNF particles remained dispersed in the nanofluid due to the weakened van der Waals interaction. The dispersion of CNF particles was improved by the presence of PVP, which further stabilised the CNF-based nanofluids. Ultimately, the thermal conductivity of the surface-oxidised CNF-based nanofluid with PVP was significantly improved with the highest enhancement percentage of 18.50, 16.84, and 19.83% at 6, 25, and 40 °C, respectively, at an optimum CNF concentration of 0.7 wt.%. Full article

(This article belongs to the Special Issue Fiber Reinforced Polymer Nanocomposites)

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12 pages, 3259 KiB

Open AccessArticle

Improved Dehydrogenation Properties of LiAlH₄ by Addition of Nanosized CoTiO₃

by Nurul Amirah Ali, Muhammad Amirul Nawi Ahmad, Muhammad Syarifuddin Yahya, Noratiqah Sazelee and Mohammad Ismail

Nanomaterials 2022, 12(21), 3921; https://doi.org/10.3390/nano12213921 - 07 Nov 2022

Cited by 9 | Viewed by 1315

Abstract

Despite the application of lithium aluminium hydride (LiAlH₄) being hindered by its sluggish desorption kinetics and unfavourable reversibility, LiAlH₄ has received special attention as a promising solid-state hydrogen storage material due to its hydrogen storage capacity (10.5 wt.%). In this [...] Read more.

Despite the application of lithium aluminium hydride (LiAlH₄) being hindered by its sluggish desorption kinetics and unfavourable reversibility, LiAlH₄ has received special attention as a promising solid-state hydrogen storage material due to its hydrogen storage capacity (10.5 wt.%). In this work, investigated for the first time was the effect of the nanosized cobalt titanate (CoTiO₃) which was synthesised via a solid-state method on the desorption behaviour of LiAlH₄. Superior desorption behaviour of LiAlH₄ was attained with the presence of a CoTiO₃ additive. By means of the addition of 5, 10, 15 and 20 wt.% of CoTiO₃, the initial desorption temperature of LiAlH₄ for the first stage was reduced to around 115–120 °C and the second desorption stage was reduced to around 144–150 °C, much lower than for undoped LiAlH₄. The LiAlH₄-CoTiO₃ sample also presents outstanding desorption kinetics behaviour, desorbing hydrogen 30–35 times faster than undoped LiAlH₄. The LiAlH₄-CoTiO₃ sample could desorb 3.0–3.5 wt.% H₂ in 30 min, while the commercial and milled LiAlH₄ desorbs <0.1 wt.% H₂. The apparent activation energy of the LiAlH₄-CoTiO₃ sample based on the Kissinger analysis was decreased to 75.2 and 91.8 kJ/mol for the first and second desorption stage, respectively, lower by 28.0 and 24.9 kJ/mol than undoped LiAlH₄. The LiAlH₄-CoTiO₃ sample presents uniform and smaller particle size distribution compared to undoped LiAlH₄, which is irregular in shape with some agglomerations. The experimental results suggest that the CoTiO₃ additive promoted notable advancements in the desorption performance of LiAlH₄ through the in situ-formed AlTi and amorphous Co or Co-containing active species that were generated during the desorption process. Full article

(This article belongs to the Special Issue Advancing the Role of Nanomaterials Innovation and Technology to Reach a Sustainable World)

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12 pages, 4574 KiB

Open AccessArticle

Preparation of UV-Curable Nano-WO₃Coating and Its Infrared Shielding Properties

by Zhengjie Wang, Rong Zhong, Ting Lai and Tianlei Chen

Nanomaterials 2022, 12(21), 3920; https://doi.org/10.3390/nano12213920 - 07 Nov 2022

Cited by 2 | Viewed by 1357

Abstract

Nano-WO₃ particles are expected to find use in new shielding materials because of their significant absorption of near-infrared light in the 1400–1600 nm and 1900–2200 nm bands and high transmittance of visible light. In this study, WO₃ was ground and dispersed [...] Read more.

Nano-WO₃ particles are expected to find use in new shielding materials because of their significant absorption of near-infrared light in the 1400–1600 nm and 1900–2200 nm bands and high transmittance of visible light. In this study, WO₃ was ground and dispersed using high-energy ball-milling to prepare a nano-WO₃ dispersion using BYK331 as the dispersant and ethanol as the solvent. The prepared nano-WO₃ dispersion was added to a photo-curing system and cured using UV irradiation to form films. The cured films were characterized using FT-IR, SEM, XRD, and TGA. The results showed that the nano-WO₃ powder was evenly dispersed in the coating. The infrared blocking rate of the film continuously improved and the visible light transmission rate continuously decreased with increasing amounts of nano-WO₃.For the film containing 6 wt%nano-WO₃, the infrared blocking rate of the coating is 90%, the visible light transmittance is 70%, the hardness of the coating is 3B, and the adhesion is 3H. The thermal stability of the coating is also improved. Full article

(This article belongs to the Special Issue Hybrid Nano Polymer Composites)

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11 pages, 2021 KiB

Open AccessArticle

A Study of the Structural and Surface Morphology and Photoluminescence of Ni-Doped AlN Thin Films Grown by Co-Sputtering

by Mohsin Khan, Ghazi Aman Nowsherwan, Aqeel Ahmed Shah, Saira Riaz, Muhammad Riaz, Ali Dad Chandio, Abdul Karim Shah, Iftikhar Ahmed Channa, Syed Sajjad Hussain, Rashid Ali, Shahzad Naseem, Muhammad Ali Shar and Abdulaziz Alhazaa

Nanomaterials 2022, 12(21), 3919; https://doi.org/10.3390/nano12213919 - 07 Nov 2022

Cited by 2 | Viewed by 2072

Abstract

Aluminum nitride (AlN) is a semiconductor material possessing a hexagonal wurtzite crystal structure with a large band gap of 6.2 eV. AlN thin films have several potential applications and areas for study, particularly in optoelectronics. This research study focused on the preparation of [...] Read more.

Aluminum nitride (AlN) is a semiconductor material possessing a hexagonal wurtzite crystal structure with a large band gap of 6.2 eV. AlN thin films have several potential applications and areas for study, particularly in optoelectronics. This research study focused on the preparation of Ni-doped AlN thin films by using DC and RF magnetron sputtering for optoelectronic applications. Additionally, a comparative analysis was also carried out on the as-deposited and annealed thin films. Several spectroscopy and microscopy techniques were considered for the characterization of structural (X-ray diffraction), morphological (SEM), chemical bonding (FTIR), and emission (PL spectroscopy) properties. The XRD results show that the thin films have an oriented c-axis hexagonal structure. SEM analysis validated the granular-like morphology of the deposited sample, and FTIR results confirm the presence of chemical bonding in deposited thin films. The photoluminescence (PL) emission spectra exhibit different peaks in the visible region when excited at different wavelengths. A sharp and intense photoluminescence peak was observed at 426 nm in the violet-blue region, which can be attributed to inter-band transitions due to the incorporation of Ni in AlN. Most of the peaks in the PL spectra occurred due to direct-band recombination and indirect impurity-band recombination. After annealing, the intensity of all observed peaks increases drastically due to the development of new phases, resulting in a decrease in defects and a corresponding increase in the crystallinity of the thin film. The observed structural, morphological, and photoluminescence results suggest that Ni: AlN is a promising candidate to be used in optoelectronics applications, specifically in photovoltaic devices and lasers. Full article

(This article belongs to the Special Issue Thin Films Based on Nanocomposites II)

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15 pages, 1991 KiB

Open AccessArticle

Co-Treatment of Caco-2 Cells with Doxorubicin and Gold Nanoparticles Produced from Cyclopia intermedia Extracts or Mangiferin Enhances Drug Effects

by Jumoke A. Aboyewa, Nicole R. S. Sibuyi, Mediline Goboza, Lee-Ann Murtz, Oluwafemi O. Oguntibeju and Mervin Meyer

Nanomaterials 2022, 12(21), 3918; https://doi.org/10.3390/nano12213918 - 07 Nov 2022

Cited by 3 | Viewed by 1780

Abstract

Mangiferin (MGF) is a natural and valuable polyphenol found in significant levels in many plant species, including Cyclopia intermedia (C. intermedia). In a previous study, we synthesized gold nanoparticles (AuNPs) using MGF and a water extract of C. intermedia and reported [...] Read more.

Mangiferin (MGF) is a natural and valuable polyphenol found in significant levels in many plant species, including Cyclopia intermedia (C. intermedia). In a previous study, we synthesized gold nanoparticles (AuNPs) using MGF and a water extract of C. intermedia and reported that these AuNPs have very low cytotoxicity toward a human colon cancer (Caco-2) cell line. Although the study also showed that these biogenic AuNPs in combination with doxorubic (DOX) significantly augmented the cytotoxic effects of DOX in Caco-2 cells, the mechanism of the enhanced effect was not fully understood, and it was also not known if other cell lines would be sensitive to this co-treatment. In the present study, we examined the cytotoxicity of the co-treatment in Caski, HeLa, HT-29, KMST-6 and MDA-321 cell lines. Additionally, we investigated the mechanistic effects of this co-treatment in Caco-2 cells using several assays, including the adenosine triphosphate (ATP), the oxidative stress, the mitochondrial depolarization, the colony formation, the APOPercentage and the DNA fragmentation assays. We also assessed the intracellular uptake of the biogenic AuNPs. The study showed that the biogenic AuNPs were effectively taken up by the cancer cells, which, in turn, may have enhanced the sensitivity of Caco-2 cells to DOX. Moreover, the combination of the biogenic AuNPs and DOX caused a rapid depletion of ATP levels, increased mitochondrial depolarization, induced apoptosis, reduced the production of reactive oxygen species (ROS) and inhibited the long-term survival of Caco-2 cells. Although the study provided some insight into the mechanism of cytotoxicity induced by the co-treatment, further mechanistic and molecular studies are required to fully elucidate the enhanced anticancer effect of the co-treatment. Full article

(This article belongs to the Special Issue Nanotechnologies for Biomedical Applications in Biosensors and Devices)

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15 pages, 2590 KiB

Open AccessEditor’s ChoiceArticle

Design and Development of Magnetic Iron Core Gold Nanoparticle-Based Fluorescent Multiplex Assay to Detect Salmonella

by Xinyi Zhao, Gwendoline Smith, Bilal Javed, Garret Dee, Yurii K. Gun’ko, James Curtin, Hugh J. Byrne, Christine O’Connor and Furong Tian

Nanomaterials 2022, 12(21), 3917; https://doi.org/10.3390/nano12213917 - 07 Nov 2022

Cited by 6 | Viewed by 1800

Abstract

Salmonella is a bacterial pathogen which is one of the leading causes of severe illnesses in humans. The current study involved the design and development of two methods, respectively using iron oxide nanoparticle (IONP) and iron core gold nanoparticle (ICGNP), conjugated with the [...] Read more.

Salmonella is a bacterial pathogen which is one of the leading causes of severe illnesses in humans. The current study involved the design and development of two methods, respectively using iron oxide nanoparticle (IONP) and iron core gold nanoparticle (ICGNP), conjugated with the Salmonella antibody and the fluorophore, 4-Methylumbelliferyl Caprylate (4-MUCAP), used as an indicator, for its selective and sensitive detection in contaminated food products. Twenty double-blind beverage samples, spiked with Salmonella enteritidis, Staphylococcus aureus, and Escherichia coli, were prepared in sterile Eppendorf^® tubes at room temperature. The gold layer and spikes of ICGNPs increased the surface areas. The ratio of the surface area is 0.76 (IONPs/ICGNPs). The comparative sensitivity and specificity of the IONP-based and the ICGNP-based methods to detect Salmonella were determined. The ICGNP method shows the limit of detection is 32 Salmonella per mL. The ICGNPs had an 83.3% sensitivity and a 92.9% specificity value for the presence and detection of Salmonella. The IONP method resulted in a limit of detection of 150 Salmonella per mL, and a 66.7% sensitivity and 83.3% specificity for the presence and detection of Salmonella. The higher surface area of ICGNPs increases the efficiency of detection. The monitoring of Salmonella can thus be achieved by a rapid magnetic fluorescent assay using a smartphone for image capture and analyze, providing quantitative results. The findings from the present study would help to detect Salmonella rapidly in water. It can improve the microbial quality of water and food safety due to the presence of Salmonella in the water environment. Full article

(This article belongs to the Special Issue Nanostructured Materials and Their Composites for Biosensing Applications)

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10 pages, 2397 KiB

Open AccessArticle

Organic Solar Cells Improved by Optically Resonant Silicon Nanoparticles

by Maria Sandzhieva, Darya Khmelevskaia, Dmitry Tatarinov, Lev Logunov, Kirill Samusev, Alexander Kuchmizhak and Sergey V. Makarov

Nanomaterials 2022, 12(21), 3916; https://doi.org/10.3390/nano12213916 - 06 Nov 2022

Cited by 5 | Viewed by 2601

Abstract

Silicon nanophotonics has become a versatile platform for optics and optoelectronics. For example, strong light localization at the nanoscale and lack of parasitic losses in infrared and visible spectral ranges make resonant silicon nanoparticles a prospect for improvement in such rapidly developing fields [...] Read more.

Silicon nanophotonics has become a versatile platform for optics and optoelectronics. For example, strong light localization at the nanoscale and lack of parasitic losses in infrared and visible spectral ranges make resonant silicon nanoparticles a prospect for improvement in such rapidly developing fields as photovoltaics. Here, we employed optically resonant silicon nanoparticles produced by laser ablation for boosting the power conversion efficiency of organic solar cells. Namely, we created colloidal solutions of spherical nanoparticles with a range of diameters (80–240 nm) in different solvents. We tested how the nanoparticles’ position in the device, their concentration, silicon doping, and method of deposition affected the final device efficiency. The best conditions optimization resulted in an efficiency improvement from 6% up to 7.5%, which correlated with numerical simulations of nanoparticles’ optical properties. The developed low-cost approach paves the way toward highly efficient and stable solution-processable solar cells. Full article

(This article belongs to the Special Issue Laser Synthesis and Processing of Nanostructured Materials)

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25 pages, 2393 KiB

Open AccessReview

Nanoparticles: The Plant Saviour under Abiotic Stresses

by Muhammad Fasih Khalid, Rashid Iqbal Khan, Muhammad Zaid Jawaid, Waqar Shafqat, Sajjad Hussain, Talaat Ahmed, Muhammad Rizwan, Sezai Ercisli, Oana Lelia Pop and Romina Alina Marc

Nanomaterials 2022, 12(21), 3915; https://doi.org/10.3390/nano12213915 - 06 Nov 2022

Cited by 41 | Viewed by 5418

Abstract

Climate change significantly affects plant growth and productivity by causing different biotic and abiotic stresses to plants. Among the different abiotic stresses, at the top of the list are salinity, drought, temperature extremes, heavy metals and nutrient imbalances, which contribute to large yield [...] Read more.

Climate change significantly affects plant growth and productivity by causing different biotic and abiotic stresses to plants. Among the different abiotic stresses, at the top of the list are salinity, drought, temperature extremes, heavy metals and nutrient imbalances, which contribute to large yield losses of crops in various parts of the world, thereby leading to food insecurity issues. In the quest to improve plants’ abiotic stress tolerance, many promising techniques are being investigated. These include the use of nanoparticles, which have been shown to have a positive effect on plant performance under stress conditions. Nanoparticles can be used to deliver nutrients to plants, overcome plant diseases and pathogens, and sense and monitor trace elements that are present in soil by absorbing their signals. A better understanding of the mechanisms of nanoparticles that assist plants to cope with abiotic stresses will help towards the development of more long-term strategies against these stresses. However, the intensity of the challenge also warrants more immediate approaches to mitigate these stresses and enhance crop production in the short term. Therefore, this review provides an update of the responses (physiological, biochemical and molecular) of plants affected by nanoparticles under abiotic stress, and potentially effective strategies to enhance production. Taking into consideration all aspects, this review is intended to help researchers from different fields, such as plant science and nanoscience, to better understand possible innovative approaches to deal with abiotic stresses in agriculture. Full article

(This article belongs to the Special Issue Nano-Bioremediation Approaches for Degraded Soils and Sustainable Crop Production)

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14 pages, 5732 KiB

Open AccessArticle

Automated Recognition of Nanoparticles in Electron Microscopy Images of Nanoscale Palladium Catalysts

by Daniil A. Boiko, Valentina V. Sulimova, Mikhail Yu. Kurbakov, Andrei V. Kopylov, Oleg S. Seredin, Vera A. Cherepanova, Evgeniy O. Pentsak and Valentine P. Ananikov

Nanomaterials 2022, 12(21), 3914; https://doi.org/10.3390/nano12213914 - 06 Nov 2022

Cited by 2 | Viewed by 1857

Abstract

Automated computational analysis of nanoparticles is the key approach urgently required to achieve further progress in catalysis, the development of new nanoscale materials, and applications. Analysis of nanoscale objects on the surface relies heavily on scanning electron microscopy (SEM) as the experimental analytic [...] Read more.

Automated computational analysis of nanoparticles is the key approach urgently required to achieve further progress in catalysis, the development of new nanoscale materials, and applications. Analysis of nanoscale objects on the surface relies heavily on scanning electron microscopy (SEM) as the experimental analytic method, allowing direct observation of nanoscale structures and morphology. One of the important examples of such objects is palladium on carbon catalysts, allowing access to various chemical reactions in laboratories and industry. SEM images of Pd/C catalysts show a large number of nanoparticles that are usually analyzed manually. Manual analysis of a statistically significant number of nanoparticles is a tedious and highly time-consuming task that is impossible to perform in a reasonable amount of time for practically needed large amounts of samples. This work provides a comprehensive comparison of various computer vision methods for the detection of metal nanoparticles. In addition, multiple new types of data representations were developed, and their applicability in practice was assessed. Full article

(This article belongs to the Special Issue Nanomaterials with Controlled Morphology for Use in Catalysis and Biological Fields)

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13 pages, 15815 KiB

Open AccessEditor’s ChoiceArticle

Fe₃O₄-Nanoparticle-Doped Epoxy Resin as a Detachable Adhesive by Electromagnetic Heating for GFRP Single-Lap Joints

by Xoan F. Sánchez-Romate, Antonio del Bosque, Anabel Crespo, Rafael Alonso, María Sánchez and Alejandro Ureña

Nanomaterials 2022, 12(21), 3913; https://doi.org/10.3390/nano12213913 - 06 Nov 2022

Cited by 1 | Viewed by 1266

Abstract

An adhesive based on a Fe₃O₄-nanoparticle (MNP)-doped epoxy resin was proposed for the development of detachable adhesive joints with GFRP substrates. The analysis of cryofractures showed that the increasing MNP content promotes a higher presence of larger aggregates and [...] Read more.

An adhesive based on a Fe₃O₄-nanoparticle (MNP)-doped epoxy resin was proposed for the development of detachable adhesive joints with GFRP substrates. The analysis of cryofractures showed that the increasing MNP content promotes a higher presence of larger aggregates and a lower sedimentation of nanoparticles due to the higher viscosity of the mixture. In this regard, the inclusion of expandable microspheres (MS) induces a more uniform dispersion of MNPs, reducing their sedimentation. The capability of the proposed adhesives for electromagnetic (EM) heating was also evaluated, with increases in temperature of around 100 °C at 750 A, enough to reach the T_g of the polymer required to facilitate the adhesive detachment, which is around 80 °C. Finally, the lap shear strength (LSS) of 14 and 20 wt.% MNP samples was evaluated in a single-lap shear joint with simultaneous EM heating. The LSS values were reduced by 60–80% at 750 A, thus promoting successful adhesive joint detachment under EM heating. Full article

(This article belongs to the Section Nanocomposite Materials)

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12 pages, 3622 KiB

Open AccessArticle

Competition between Ferroelectric and Ferroelastic Domain Wall Dynamics during Local Switching in Rhombohedral PMN-PT Single Crystals

by Denis Alikin, Anton Turygin, Andrei Ushakov, Mikhail Kosobokov, Yurij Alikin, Qingyuan Hu, Xin Liu, Zhuo Xu, Xiaoyong Wei and Vladimir Shur

Nanomaterials 2022, 12(21), 3912; https://doi.org/10.3390/nano12213912 - 06 Nov 2022

Cited by 2 | Viewed by 1717

Abstract

The possibility to control the charge, type, and density of domain walls allows properties of ferroelectric materials to be selectively enhanced or reduced. In ferroelectric–ferroelastic materials, two types of domain walls are possible: pure ferroelectric and ferroelastic–ferroelectric. In this paper, we demonstrated a [...] Read more.

The possibility to control the charge, type, and density of domain walls allows properties of ferroelectric materials to be selectively enhanced or reduced. In ferroelectric–ferroelastic materials, two types of domain walls are possible: pure ferroelectric and ferroelastic–ferroelectric. In this paper, we demonstrated a strategy to control the selective ferroelectric or ferroelastic domain wall formation in the (111) single-domain rhombohedral PMN-PT single crystals at the nanoscale by varying the relative humidity level in a scanning probe microscopy chamber. The solution of the corresponding coupled electro-mechanical boundary problem allows explaining observed competition between ferroelastic and ferroelectric domain growth. The reduction in the ferroelastic domain density during local switching at elevated humidity has been attributed to changes in the electric field spatial distribution and screening effectiveness. The established mechanism is important because it reveals a kinetic nature of the final domain patterns in multiaxial materials and thus provides a general pathway to create desirable domain structure in ferroelectric materials for applications in piezoelectric and optical devices. Full article

(This article belongs to the Special Issue Advanced Piezoelectric Materials for Applications)

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13 pages, 3347 KiB

Open AccessFeature PaperArticle

Bismuth Quantum Dot (Bi QD)/Polydimethylsiloxane (PDMS) Nanocomposites with Self-Cleaning and Antibacterial Activity for Dental Applications

by Yingzi Hu, Zhiliang Xu, Yi Hu, Lanping Hu, You Zi, Mengke Wang, Xingmei Feng and Weichun Huang

Nanomaterials 2022, 12(21), 3911; https://doi.org/10.3390/nano12213911 - 05 Nov 2022

Cited by 6 | Viewed by 1877

Abstract

In the oral microenvironment, bacteria colonies are easily aggregated on the tooth-restoration surface, in the manner of a biofilm, which usually consists of heterogeneous structures containing clusters of a variety of bacteria embedded in an extracellular matrix, leading to serious recurrent caries. In [...] Read more.

In the oral microenvironment, bacteria colonies are easily aggregated on the tooth-restoration surface, in the manner of a biofilm, which usually consists of heterogeneous structures containing clusters of a variety of bacteria embedded in an extracellular matrix, leading to serious recurrent caries. In this contribution, zero-dimensional (0D) bismuth (Bi) quantum dots (QDs) synthesized by a facile solvothermal method were directly employed to fabricate a Bi QD/polydimethylsiloxane (PDMS)-modified tooth by simple curing treatment. The result demonstrates that the as-fabricated Bi QD/PDMS-modified tooth at 37 °C for 120 min not only showed significantly improved hydrophobic performance with a water contact angle of 103° and 115° on the tooth root and tooth crown, respectively, compared to that (~20° on the tooth root, and ~5° on the tooth crown) of the pristine tooth, but also exhibited excellent antibacterial activity against S. mutans, superior biocompatibility, and biosafety. In addition, due to the highly photothermal effect of Bi QDs, the antibacterial activity of the as-fabricated Bi QD/PDMS-modified tooth could be further enhanced under illumination, even at a very low power density (12 mW cm⁻²). Due to the facile fabrication, excellent hydrophobicity, superior antibacterial activity, and biocompatibility and biosafety of the Bi QD/PDMS-modified tooth, it is envisioned that the Bi QD/PDMS-modified tooth with a fascinating self-cleaning and antibacterial performance can pave the way to new designs of versatile multifunctional nanocomposites to prevent secondary caries in the application of dental restoration. Full article

(This article belongs to the Special Issue Xene-Related Nanostructures for Versatile Applications)

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12 pages, 2934 KiB

Open AccessEditor’s ChoiceArticle

Reduced Thermal Conductivity in Nanostructured AgSbTe₂ Thermoelectric Material, Obtained by Arc-Melting

by Javier Gainza, Federico Serrano-Sánchez, Oscar J. Dura, Norbert M. Nemes, Jose Luis Martínez, María Teresa Fernández-Díaz and José Antonio Alonso

Nanomaterials 2022, 12(21), 3910; https://doi.org/10.3390/nano12213910 - 05 Nov 2022

Cited by 1 | Viewed by 1734

Abstract

AgSbTe₂ intermetallic compound is a promising thermoelectric material. It has also been described as necessary to obtain LAST and TAGS alloys, some of the best performing thermoelectrics of the last decades. Due to the random location of Ag and Sb atoms in [...] Read more.

AgSbTe₂ intermetallic compound is a promising thermoelectric material. It has also been described as necessary to obtain LAST and TAGS alloys, some of the best performing thermoelectrics of the last decades. Due to the random location of Ag and Sb atoms in the crystal structure, the electronic structure is highly influenced by the atomic ordering of these atoms and makes the accurate determination of the Ag/Sb occupancy of paramount importance. We report on the synthesis of polycrystalline AgSbTe₂ by arc-melting, yielding nanostructured dense pellets. SEM images show a conspicuous layered nanostructuration, with a layer thickness of 25–30 nm. Neutron powder diffraction data show that AgSbTe₂ crystalizes in the cubic Pm-3m space group, with a slight deficiency of Te, probably due to volatilization during the arc-melting process. The transport properties show some anomalies at ~600 K, which can be related to the onset temperature for atomic ordering. The average thermoelectric figure of merit remains around ~0.6 from ~550 up to ~680 K. Full article

(This article belongs to the Special Issue Advanced Nanoscale Materials for Thermoelectric Applications)

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14 pages, 4538 KiB

Open AccessArticle

Microstructure, Mechanical and Tribological Properties of Arc Ion Plating NbN-Based Nanocomposite Films

by Yingying Fu, Hongxuan Li, Jianmin Chen, Hongjian Guo and Xiang Wang

Nanomaterials 2022, 12(21), 3909; https://doi.org/10.3390/nano12213909 - 05 Nov 2022

Cited by 1 | Viewed by 1306

Abstract

NbN, NbN-Ag and NbN/NbN-Ag multilayer nanocomposite films were successfully deposited by an arc ion plating system (AIP), and their microstructures, mechanical and tribological properties were systematically investigated. The results show that all the films had a polycrystalline structure, and the Ag in the [...] Read more.

NbN, NbN-Ag and NbN/NbN-Ag multilayer nanocomposite films were successfully deposited by an arc ion plating system (AIP), and their microstructures, mechanical and tribological properties were systematically investigated. The results show that all the films had a polycrystalline structure, and the Ag in the Ag-doped films existed independently as a face-centered cubic phase. The content of Ag in NbN-Ag and NbN/NbN-Ag films was 20.11 and 9.07 at.%, respectively. NbN films fabricated by AIP technique had excellent mechanical properties, and their hardness and critical load were up to 44 GPa and 34.6 N, respectively. The introduction of Ag into NbN films obviously reduced the friction coefficient at room temperature, while the mechanical properties and wear resistance were degraded sharply in comparison with that of NbN films. However, the NbN/NbN-Ag films presented better hardness, H/E*, H³/E*², adhesive strength and wear resistance than NbN-Ag films. Additionally, analysis of wear surfaces of the studied films and Al₂O₃ balls using 3D images, depth profiles, energy dispersive spectrometry (EDS) and Raman spectra indicated that the main wear mechanisms of NbN and NbN/NbN-Ag films were adhesive and oxidation wear with slight abrasive wear, while the severe abrasive and oxidation wear were the dominant wear mechanism for NbN-Ag films. Full article

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31 pages, 2835 KiB

Open AccessFeature PaperReview

Diverse Pathways of Engineered Nanoparticle-Induced NLRP3 Inflammasome Activation

by Xin Liao, Yudong Liu, Jiarong Zheng, Xinyuan Zhao, Li Cui, Shen Hu, Tian Xia and Shanshan Si

Nanomaterials 2022, 12(21), 3908; https://doi.org/10.3390/nano12213908 - 05 Nov 2022

Cited by 1 | Viewed by 2117

Abstract

With the rapid development of engineered nanomaterials (ENMs) in biomedical applications, their biocompatibility and cytotoxicity need to be evaluated properly. Recently, it has been demonstrated that inflammasome activation may be a vital contributing factor for the development of biological responses induced by ENMs. [...] Read more.

With the rapid development of engineered nanomaterials (ENMs) in biomedical applications, their biocompatibility and cytotoxicity need to be evaluated properly. Recently, it has been demonstrated that inflammasome activation may be a vital contributing factor for the development of biological responses induced by ENMs. Among the inflammasome family, NLRP3 inflammasome has received the most attention because it directly interacts with ENMs to cause the inflammatory effects. However, the pathways that link ENMs to NLRP3 inflammasome have not been thoroughly summarized. Thus, we reviewed recent findings on the role of major ENMs properties in modulating NLRP3 inflammasome activation, both in vitro and in vivo, to provide a better understanding of the underlying mechanisms. In addition, the interactions between ENMs and NLRP3 inflammasome activation are summarized, which may advance our understanding of safer designs of nanomaterials and ENM-induced adverse health effects. Full article

(This article belongs to the Special Issue Towards a Safe Nanotechnology: Understanding and Controlling Immunomodulatory and Toxicological Properties of Nanomaterials)

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16 pages, 2866 KiB

Open AccessArticle

Accurate and Comprehensive Spectrum Characterization for Cavity-Enhanced Electro-Optic Comb Generators

by Ruitao Yang, Jinxuan Wu, Hongxing Yang, Haijin Fu, Liang Yu, Xu Xing, Yisi Dong, Pengcheng Hu and Jiubin Tan

Nanomaterials 2022, 12(21), 3907; https://doi.org/10.3390/nano12213907 - 05 Nov 2022

Viewed by 1293

Abstract

Cavity-enhanced electro-optic comb generators (CEEOCGs) can provide optical frequency combs with excellent stability and configurability. The existing methods for CEEOCGs spectrum characterization, however, are based on approximations and have suffered from either iterative calculations or limited applicable conditions. In this paper, we show [...] Read more.

Cavity-enhanced electro-optic comb generators (CEEOCGs) can provide optical frequency combs with excellent stability and configurability. The existing methods for CEEOCGs spectrum characterization, however, are based on approximations and have suffered from either iterative calculations or limited applicable conditions. In this paper, we show a spectrum characterization method by accumulating the optical electrical field with respect to the count of the round-trip propagation inside of CEEOCGs. The identity transformation and complete analysis of the intracavity phase delay were conducted to eliminate approximations and be applicable to arbitrary conditions, respectively. The calculation efficiency was improved by the noniterative matrix operations. Setting the maximum propagation count as 1000, the spectrum of the center ±300 comb modes can be characterized with merely the truncation error of floating-point numbers within 1.2 s. More importantly, the effects of all CEEOCG parameters were comprehensively characterized for the first time. Accordingly, not only the exact working condition of CEEOCG can be identified for further optimization, but also the power of each comb mode can be predicted accurately and efficiently for applications in optical communications and waveform synthesis. Full article

(This article belongs to the Special Issue Nanophotonics: Lasers, Gratings and Localized Surface Plasmons)

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18 pages, 4629 KiB

Open AccessArticle

Improvement of Photocatalytic Performance by Building Multiple Heterojunction Structures of Anatase–Rutile/BiOI Composite Fibers

by Dayu Li, Kai Xu and Chao Zhang

Nanomaterials 2022, 12(21), 3906; https://doi.org/10.3390/nano12213906 - 05 Nov 2022

Cited by 6 | Viewed by 1249

Abstract

In this study, multiple heterojunction structures of anatase–rutile/Bismuth oxyiodide (BiOI) composite fibers are designed by the combined method of electrospinning and hydrothermal techniques. The influence of different Ti/Bi atomic ratios ([Ti/Bi]) on the nanostructures and photocatalytic properties are investigated. It is found that [...] Read more.

In this study, multiple heterojunction structures of anatase–rutile/Bismuth oxyiodide (BiOI) composite fibers are designed by the combined method of electrospinning and hydrothermal techniques. The influence of different Ti/Bi atomic ratios ([Ti/Bi]) on the nanostructures and photocatalytic properties are investigated. It is found that the morphology of BiOI covered on the TiO₂ fiber surface changed with [Ti/Bi] from nanosheets to submicron spheres structures. Additionally, the crystallization of the composite fibers including the phases of anatase, rutile, and BiOI is identified, theses phases are in close contact with each other, and the interfacial effects are helpful to form the multiple heterojunctions which lead to blue shifts on the chemical state of Ti. The absorption of visible light has been improved by compositing BiOI on TiO₂, while the band gap values of the composite fibers are significantly reduced, which can enhance the generation and separation of electrons and holes. For the case of [Ti/Bi] = 1.57, the photodegradation rate of anatase–rutile/BiOI composite fibers is about 12 times that of pure TiO₂. For the photocatalytic mechanism, the synergistic s-type heterojunctions increase the content of active oxides which have a positive effect on the degradation rate. Full article

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28 pages, 4668 KiB

Open AccessReview

Bioresource-Functionalized Quantum Dots for Energy Generation and Storage: Recent Advances and Feature Perspective

by Seyyed Mojtaba Mousavi, Seyyed Alireza Hashemi, Masoomeh Yari Kalashgrani, Darwin Kurniawan, Ahmad Gholami and Wei-Hung Chiang

Nanomaterials 2022, 12(21), 3905; https://doi.org/10.3390/nano12213905 - 05 Nov 2022

Cited by 3 | Viewed by 1947

Abstract

The exponential increase in global energy demand in daily life prompts us to search for a bioresource for energy production and storage. Therefore, in developing countries with large populations, there is a need for alternative energy resources to compensate for the energy deficit [...] Read more.

The exponential increase in global energy demand in daily life prompts us to search for a bioresource for energy production and storage. Therefore, in developing countries with large populations, there is a need for alternative energy resources to compensate for the energy deficit in an environmentally friendly way and to be independent in their energy demands. The objective of this review article is to compile and evaluate the progress in the development of quantum dots (QDs) for energy generation and storage. Therefore, this article discusses the energy scenario by presenting the basic concepts and advances of various solar cells, providing an overview of energy storage systems (supercapacitors and batteries), and highlighting the research progress to date and future opportunities. This exploratory study will examine the systematic and sequential advances in all three generations of solar cells, namely perovskite solar cells, dye-sensitized solar cells, Si cells, and thin-film solar cells. The discussion will focus on the development of novel QDs that are economical, efficient, and stable. In addition, the current status of high-performance devices for each technology will be discussed in detail. Finally, the prospects, opportunities for improvement, and future trends in the development of cost-effective and efficient QDs for solar cells and storage from biological resources will be highlighted. Full article

(This article belongs to the Special Issue Advances in Micro/Nanofluidic Power)

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12 pages, 5720 KiB

Open AccessArticle

Janus Type Monolayers of S-MoSiN₂ Family and Van Der Waals Heterostructures with Graphene: DFT-Based Study

by Ruslan M. Meftakhutdinov and Renat T. Sibatov

Nanomaterials 2022, 12(21), 3904; https://doi.org/10.3390/nano12213904 - 05 Nov 2022

Cited by 1 | Viewed by 1488

Abstract

Novel representative 2D materials of the Janus type family X-M-ZN

_{2}

are studied. These materials are hybrids of a transition metal dichalcogenide and a material from the MoSi

_{2}

N

_{4}

family, and they were constructed and optimized from the MoSi

_{2}

N [...] Read more.

Novel representative 2D materials of the Janus type family X-M-ZN

_{2}

are studied. These materials are hybrids of a transition metal dichalcogenide and a material from the MoSi

_{2}

N

_{4}

family, and they were constructed and optimized from the MoSi

_{2}

N

_{4}

monolayer by the substitution of SiN

_{2}

group on one side by chalcogen atoms (sulfur, selenium, or tellurium), and possibly replacing molybdenum (Mo) to tungsten (W) and/or silicon (Si) to germanium (Ge). The stability of novel materials is evaluated by calculating phonon spectra and binding energies. Mechanical, electronic, and optical characteristics are calculated by methods based on the density functional theory. All considered 2D materials are semiconductors with a substantial bandgap (>1 eV). The mirror symmetry breaking is the cause of a significant built-in electric field and intrinsic dipole moment. The spin–orbit coupling (SOC) is estimated by calculations of SOC polarized bandstructures for four most stable X-M-ZN

_{2}

structures. The possible van der Waals heterostructures of considered Janus type monolayers with graphene are constructed and optimized. It is demonstrated that monolayers can serve as outer plates in conducting layers (with graphene) for shielding a constant external electric field. Full article

(This article belongs to the Special Issue Application of Functionalized Two-Dimensional Nanomaterials in Energy Storage and Catalysis)

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18 pages, 4748 KiB

Open AccessArticle

Electrospun Poly(acrylic acid-co-4-styrene sulfonate) as Potential Drug-Eluting Scaffolds for Targeted Chemotherapeutic Delivery Systems on Gastric (AGS) and Breast (MDA-Mb-231) Cancer Cell Lines

by Andrónico Neira-Carrillo, Ignacio A. Zárate, Eddie Nieto, Nicole Butto-Miranda, Lorena Lobos-González, Matias Del Campo-Smith, Daniel A. Palacio and Bruno F. Urbano

Nanomaterials 2022, 12(21), 3903; https://doi.org/10.3390/nano12213903 - 04 Nov 2022

Cited by 2 | Viewed by 1616

Abstract

Potential drug-eluting scaffolds of electrospun poly(acrylic acid-co-styrene sulfonate) P(AA-co-SS) in clonogenic assays using tumorigenic gastric and ovarian cancer cells were tested in vitro. Electrospun polymer nanofiber (EPnF) meshes of PAA and PSSNa homo- and P(AA-co-SS) copolymer composed [...] Read more.

Potential drug-eluting scaffolds of electrospun poly(acrylic acid-co-styrene sulfonate) P(AA-co-SS) in clonogenic assays using tumorigenic gastric and ovarian cancer cells were tested in vitro. Electrospun polymer nanofiber (EPnF) meshes of PAA and PSSNa homo- and P(AA-co-SS) copolymer composed of 30:70, 50:50, 70:30 acrylic acid (AA) and sodium 4-styrene sulfonate (SSNa) units were performed by electrospinning (ES). The synthesis, structural and morphological characterization of all EPnF meshes were analyzed by optical and electron microscopy (SEM-EDS), infrared spectroscopy (FTIR), contact angle, and X-ray diffraction (XRD) measurements. This study shows that different ratio of AA and SSNa of monomers in P(AA-co-SS) EPnF play a crucial role in clonogenic in vitro assays. We found that 50:50 P(AA-co-SS) EPnF mesh loaded with antineoplastic drugs can be an excellent suppressor of growth-independent anchored capacities in vitro assays and a good subcutaneous drug delivery system for chemotherapeutic medication in vivo model for surgical resection procedures in cancer research. Full article

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12 pages, 3070 KiB

Open AccessArticle

The Mechanism of the Photostability Enhancement of Thin-Film Transistors Based on Solution-Processed Oxide Semiconductors Doped with Tetravalent Lanthanides

by Linfeng Lan, Chunchun Ding, Penghui He, Huimin Su, Bo Huang, Jintao Xu, Shuguang Zhang and Junbiao Peng

Nanomaterials 2022, 12(21), 3902; https://doi.org/10.3390/nano12213902 - 04 Nov 2022

Cited by 2 | Viewed by 1292

Abstract

The applications of thin-film transistors (TFTs) based on oxide semiconductors are limited due to instability under negative bias illumination stress (NBIS). Here, we report TFTs based on solution-processed In₂O₃ semiconductors doped with Pr⁴⁺ or Tb⁴⁺, which can [...] Read more.

The applications of thin-film transistors (TFTs) based on oxide semiconductors are limited due to instability under negative bias illumination stress (NBIS). Here, we report TFTs based on solution-processed In₂O₃ semiconductors doped with Pr⁴⁺ or Tb⁴⁺, which can effectively improve the NBIS stability. The differences between the Pr⁴⁺-doped In₂O₃ (Pr:In₂O₃) and Tb⁴⁺-doped In₂O₃ (Tb:In₂O₃) are investigated in detail. The undoped In₂O₃ TFTs with different annealing temperatures exhibit poor NBIS stability with serious turn-on voltage shift (ΔV_on). After doping with Pr⁴⁺/Tb⁴⁺, the TFTs show greatly improved NBIS stability. As the annealing temperature increases, the Pr:In₂O₃ TFTs have poorer NBIS stability (ΔV_on are −3.2, −4.8, and −4.8 V for annealing temperature of 300, 350, and 400 °C, respectively), while the Tb:In₂O₃ TFTs have better NBIS stability (ΔV_on are −3.6, −3.6, and −1.2 V for annealing temperature of 300, 350, and 400 ℃, respectively). Further studies reveal that the improvement of the NBIS stability of the Pr⁴⁺/Tb⁴⁺:In₂O₃ TFTs is attributed to the absorption of the illuminated light by the Pr/Tb4fⁿ—O2p⁶ to Pr/Tb 4fⁿ⁺¹—O2p⁵ charge transfer (CT) transition and downconversion of the light to nonradiative transition with a relatively short relaxation time compared to the ionization process of the oxygen vacancies. The higher NBIS stability of Tb:In₂O₃ TFTs compared to Pr:In₂O₃ TFTs is ascribed to the smaller ion radius of Tb⁴⁺ and the lower energy level of Tb 4f⁷ with a isotropic half-full configuration compared to that of Pr 4f¹, which would make it easier for the Tb⁴⁺ to absorb the visible light than the Pr⁴⁺. Full article

(This article belongs to the Special Issue Nanoscale Thin Film Transistors and Application Exploration)

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12 pages, 7895 KiB

Open AccessArticle

Capacitive Desalination and Disinfection of Water Using UiO-66 Metal–Organic Framework/Bamboo Carbon with Chitosan

by Cuihui Cao, Xiaofeng Wu, Yuming Zheng, Lizhen Zhang and Yunfa Chen

Nanomaterials 2022, 12(21), 3901; https://doi.org/10.3390/nano12213901 - 04 Nov 2022

Cited by 3 | Viewed by 1533

Abstract

The zirconium-based metal–organic framework (MOF) (UiO-66)/bamboo carbon (BC) composite with chitosan was prepared using hydrothermal and impregnation methods and used for capacitive desalination (CDI) and disinfection of water. The results showed that these composites had fast ion exchange and charge transfer properties. During [...] Read more.

The zirconium-based metal–organic framework (MOF) (UiO-66)/bamboo carbon (BC) composite with chitosan was prepared using hydrothermal and impregnation methods and used for capacitive desalination (CDI) and disinfection of water. The results showed that these composites had fast ion exchange and charge transfer properties. During the CDI process, these composites’ electrodes exhibited good cycle stability, electrosorption capacity (4.25 mg/g) and excellent bactericidal effect. These carbon-based composites electrodes’ bactericidal rate for Escherichia coli could reach 99.99% within 20 minutes; therefore, they had good performance and were a good choice for high-performance deionization applications. Full article

(This article belongs to the Special Issue Advanced Nanocomposite Materials for Water and Wastewater Treatment)

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14 pages, 3999 KiB

Open AccessArticle

Novel Nanosized Spinel MnCoFeO₄ for Low-Temperature Hydrocarbon Oxidation

by Vencislav Tumbalev, Daniela Kovacheva, Ivanka Spassova, Ralitsa Velinova, Georgi Tyuliev, Nikolay Velinov and Anton Naydenov

Nanomaterials 2022, 12(21), 3900; https://doi.org/10.3390/nano12213900 - 04 Nov 2022

Viewed by 1420

Abstract

The present paper reports on MnCoFeO₄ spinels with peculiar composition and their catalytic behavior in the reactions of complete oxidation of hydrocarbons. The samples were synthesized by solution combustion method with sucrose and citric acid as fuels. All samples were characterized by [...] Read more.

The present paper reports on MnCoFeO₄ spinels with peculiar composition and their catalytic behavior in the reactions of complete oxidation of hydrocarbons. The samples were synthesized by solution combustion method with sucrose and citric acid as fuels. All samples were characterized by powder X-ray diffraction, N₂-physisorption, scanning electron microscopy, thermal analysis, X-ray photoelectron spectroscopy, and Mössbauer spectroscopy. The catalytic properties of the spinels with Mn:Co:Fe = 1:1:1 composition were studied in reactions of complete oxidation of methane, propane, butane, and propane in the presence of water as model pollutants. Both prepared catalysts are nanosized materials. The slight difference in the compositions, structure, and morphology is due to the type of fuel used in the synthesis reaction. The spinel, prepared with sucrose, shows a higher specific surface area, pore volume, higher amount of small particles fraction, higher thermal stability, and as a result, more exposed active sites on the sample surface that lead to higher catalytic activity in the studied oxidation reactions. After the catalytic tests, both samples do not undergo any substantial phase and morphological changes; thus, they could be applied in low-temperature hydrocarbon oxidation reactions. Full article

(This article belongs to the Section Energy and Catalysis)

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35 pages, 32082 KiB

Open AccessReview

Surface Functionalization of Nanofibers: The Multifaceted Approach for Advanced Biomedical Applications

by Deepak Kulkarni, Shubham Musale, Prabhakar Panzade, Ana Cláudia Paiva-Santos, Pratiksha Sonwane, Monika Madibone, Puja Choundhe, Prabhanjan Giram and Simona Cavalu

Nanomaterials 2022, 12(21), 3899; https://doi.org/10.3390/nano12213899 - 04 Nov 2022

Cited by 14 | Viewed by 3183

Abstract

Nanocarriers are gaining significant importance in the modern era of drug delivery. Nanofiber technology is one of the prime paradigms in nanotechnology for various biomedical and theranostic applications. Nanofibers obtained after successful electrospinning subjected to surface functionalized for drug delivery, biomedical, tissue engineering, [...] Read more.

Nanocarriers are gaining significant importance in the modern era of drug delivery. Nanofiber technology is one of the prime paradigms in nanotechnology for various biomedical and theranostic applications. Nanofibers obtained after successful electrospinning subjected to surface functionalized for drug delivery, biomedical, tissue engineering, biosensing, cell imaging and wound dressing application. Surface functionalization entirely changes physicochemical and biological properties of nanofibers. In physicochemical properties, wettability, melting point, glass transition temperature, and initial decomposition temperature significantly change offer several advantageous for nanofibers. Similarly, biological properties include cell adhesion, biocompatibility, and proliferation, also changes by functionalization of nanofibers. Various natural and synthetic materials polymers, metals, carbon materials, functional groups, proteins, and peptides, are currently used for surface modification of nanofibers. Various research studies across the globe demonstrated the usefulness of surface functionalized nanofibers in tissue engineering, wound healing, skin cancers, melanoma, and disease diagnosis. The delivery of drug through surface functionalized nanofibers results in improved permeation and bioavailability of drug which is important for better targeting of disease and therapeutic efficacy. This review provides a comprehensive insight about various techniques of surface functionalization of nanofibers along with its biomedical applications, toxicity assessment and global patent scenario. Full article

(This article belongs to the Special Issue Surface Fabrication and Modification of Nanomaterials)

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10 pages, 5196 KiB

Open AccessEditor’s ChoiceArticle

Influence of Group-IVA Doping on Electronic and Optical Properties of ZnS Monolayer: A First-Principles Study

by Bin Liu, Wan-Sheng Su and Bi-Ru Wu

Nanomaterials 2022, 12(21), 3898; https://doi.org/10.3390/nano12213898 - 04 Nov 2022

Cited by 3 | Viewed by 1416

Abstract

Element doping is a universal way to improve the electronic and optical properties of two-dimensional (2D) materials. Here, we investigate the influence of group−ⅣA element (C, Si, Ge, Sn, and Pb) doping on the electronic and optical properties of the ZnS monolayer with [...] Read more.

Element doping is a universal way to improve the electronic and optical properties of two-dimensional (2D) materials. Here, we investigate the influence of group−ⅣA element (C, Si, Ge, Sn, and Pb) doping on the electronic and optical properties of the ZnS monolayer with a tetragonal phase by using first-principles calculations. The results indicate that the doping atoms tend to form tetrahedral structures with neighboring S atoms. In these doped models, the formation energies are all negative, indicating that the formation processes of the doped models will release energy. The formation energy is smallest for C−doped ZnS and gradually increases with the metallicity of the doping element. The doped ZnS monolayer retains a direct band gap, with this band gap changing little in other element doping cases. Moreover, intermediate states are observed that are induced by the sp³ hybridization from the doping atoms and S atoms. Such intermediate states expand the optical absorption range into the visible spectrum. Our findings provide an in-depth understanding of the electronic and optical properties of the ZnS monolayer and the associated doping structures, which is helpful for application in optoelectronic devices. Full article

(This article belongs to the Special Issue First-Principles Investigations of Low-Dimensional Nanomaterials)

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10 pages, 2437 KiB

Open AccessArticle

Ultrafast-Laser Micro-Structuring of LiNi_0.8Mn_0.1Co_0.1O₂ Cathode for High-Rate Capability of Three-Dimensional Li-ion Batteries

by Minh Xuan Tran, Peter Smyrek, Jihun Park, Wilhelm Pfleging and Joong Kee Lee

Nanomaterials 2022, 12(21), 3897; https://doi.org/10.3390/nano12213897 - 04 Nov 2022

Cited by 12 | Viewed by 1672

Abstract

Femtosecond ultrafast-laser micro-patterning was employed to prepare a three-dimensional (3D) structure for the tape-casting Ni-rich LiNi_0.8Mn_0.1Co_0.1O₂ (NMC811) cathode. The influences of laser structuring on the electrochemical performance of NMC811 were investigated. The 3D-NMC811 cathode retained capacities [...] Read more.

Femtosecond ultrafast-laser micro-patterning was employed to prepare a three-dimensional (3D) structure for the tape-casting Ni-rich LiNi_0.8Mn_0.1Co_0.1O₂ (NMC811) cathode. The influences of laser structuring on the electrochemical performance of NMC811 were investigated. The 3D-NMC811 cathode retained capacities of 77.8% at 2 C of initial capacity at 0.1 C, which was thrice that of 2D-NMC811 with an initial capacity of 27.8%. Cyclic voltammetry (CV) and impedance spectroscopy demonstrated that the 3D electrode improved the Li⁺ ion transportation at the electrode–electrolyte interface, resulting in a higher rate capability. The diffusivity coefficient D_Li+, calculated by both CV and electrochemical impedance spectroscopy, revealed that 3D-NMC811 delivered faster Li⁺ ion transportation with higher D_Li+ than that of 2D-NMC811. The laser ablation of the active material also led to a lower charge–transfer resistance, which represented lower polarization and improved Li⁺ ion diffusivity. Full article

(This article belongs to the Special Issue Functionalized Nanostructures for Novel Energy Storage Systems)

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