The Properties of Functional Nanomaterials and Their Energy and Environmental Applications

A special issue of Nanomaterials (ISSN 2079-4991). This special issue belongs to the section "Nanoelectronics, Nanosensors and Devices".

Deadline for manuscript submissions: closed (31 January 2023) | Viewed by 21267

Special Issue Editors


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Guest Editor
School of Science, Xi’an University of Posts and Telecommunications, Xi’an 710121, China
Interests: piezocatalysis; mechanocatalysis; pyrocatalysis; photocatalysis; energy harvesting
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
School of Physics and Technology, Wuhan University, Wuhan 430072, China
Interests: metal oxides; gas sensing; material failure; tribocatalysis; photocatalysis
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Ferroelectric materials exhibit not only ferroelectric phenomena but also piezoelectric, pyroelectric, and electro-optic effects, which can be used in many technological applications. Ferroelectric nanomaterials, especially ferroelectric perovskite oxides such as BaTiO3, BiFeO3, etc., have recently emerged as star materials in many fields, including in the study of photovoltaic solar cell devices, piezoelectric or pyroelectric energy conversion, energy harvesting and storage, and catalysis. The purpose of this Special Issue is to highlight recent advances in ferroelectric nanomaterials for application in energy and environmental sciences. Examples include the synthesis and characterization of novel ferroelectric/piezoelectric/pyroelectric/dielectric nanocrystals and their performance in terms of photocatalysis, photovoltaic devices, electro-optical control, capacitance, piezoelectric catalysis, pyroelectric catalysis, energy harvesting, triboelectric performance, photoluminescence, and so on. Their utilization in energy applications, such as in solar cells, supercapacitors, energy harvesters, and applications in environmental science such as dye degradation, antibacterial, water splitting into hydrogen, CO2 reduction and nitrogen fixation, etc., are also of interest.

This Special Issue covers all aspects of ferroelectric nanomaterials, including theory, synthetic efforts, novel processing methods, and the developments in application of energy and environmental sciences. Reports of novel or improved applications of ferroelectric nanomaterials in different areas are also welcome.

Prof. Dr. Yanmin Jia
Prof. Dr. Wanping Chen
Guest Editors

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Keywords

  • ferroelectric nanomaterials
  • piezoelectric nanomaterials
  • pyroelectric nanomaterials
  • dielectric nanomaterials
  • ferroelectric photocatalysis
  • piezocatalysis
  • pyroelectric catalysis
  • ferroelectric photovoltaic
  • triboelectric effect
  • triboelectric catalysis
  • ferroelectric sensors
  • ferroelectric capacitor multiferroic nanomaterials
  • piezoelectric energy harvester
  • ferroelectric storge

Published Papers (13 papers)

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Research

12 pages, 19286 KiB  
Article
Remarkable Pyro-Catalysis of g-C3N4 Nanosheets for Dye Decoloration under Room-Temperature Cold–Hot Cycle Excitation
by Zheng Wu, Xiaoyu Shi, Tingting Liu, Xiaoli Xu, Hongjian Yu, Yan Zhang, Laishun Qin, Xiaoping Dong and Yanmin Jia
Nanomaterials 2023, 13(6), 1124; https://doi.org/10.3390/nano13061124 - 21 Mar 2023
Cited by 8 | Viewed by 1394
Abstract
Pyroelectric materials have the ability to convert the environmental cold–hot thermal energy such as day–night temperature alternation into electrical energy. The novel pyro-catalysis technology can be designed and realized on the basis of the product coupling between pyroelectric and electrochemical redox effects, which [...] Read more.
Pyroelectric materials have the ability to convert the environmental cold–hot thermal energy such as day–night temperature alternation into electrical energy. The novel pyro-catalysis technology can be designed and realized on the basis of the product coupling between pyroelectric and electrochemical redox effects, which is helpful for the actual dye decomposition. The organic two-dimensional (2D) graphic carbon nitride (g-C3N4), as an analogue of graphite, has attracted considerable interest in the field of material science; however, its pyroelectric effect has rarely been reported. In this work, the remarkable pyro-catalytic performance was achieved in the 2D organic g-C3N4 nanosheet catalyst materials under the continuous room-temperature cold–hot thermal cycling excitation from 25 °C to 60 °C. The pyro-catalytic RhB dye decoloration efficiency of the 2D organic g-C3N4 can reach ~92.6%. Active species such as the superoxide radicals and hydroxyl radicals are observed as the intermediate products in the pyro-catalysis process of the 2D organic g-C3N4 nanosheets. The pyro-catalysis of the 2D organic g-C3N4 nanosheets provides efficient technology for wastewater treatment applications, utilizing the ambient cold–hot alternation temperature variations in future. Full article
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14 pages, 10088 KiB  
Article
Preparation and Thermal Conductivity Enhancement of Boron Nitride Nano-Material PiG Composite
by Zhenhua Chen, Qinhua Wei, Gao Tang, Hongsheng Shi and Laishun Qin
Nanomaterials 2023, 13(6), 1106; https://doi.org/10.3390/nano13061106 - 20 Mar 2023
Cited by 1 | Viewed by 1582
Abstract
With the improvement of the conversion efficiency of LED chip and fluorescent material and the increasing demand for high-brightness light sources, LED technology has begun to move toward the direction of high-power. However, there is a huge problem that high-power LED must face [...] Read more.
With the improvement of the conversion efficiency of LED chip and fluorescent material and the increasing demand for high-brightness light sources, LED technology has begun to move toward the direction of high-power. However, there is a huge problem that high-power LED must face with a large amount of heat generated by high power causing a high temperature thermal decay or even thermal quenching of the fluorescent material in the device, resulting in a reduction of the luminous efficiency, color coordinates, color rendering index, light uniformity, and service life of LED. In order to solve this problem, fluorescent materials with high thermal stability and better heat dissipation were prepared to enhance their performance in high-power LED environments. A variety of boron nitride nanomaterials were prepared by the solid phase-gas phase method. By adjusting the ratio of boric acid to urea in the raw material, different BN nanoparticles and nanosheets were obtained. Moreover, the control of catalyst amount and synthesis temperature can be used to synthesize boron nitride nanotubes with various morphologies. By adding different morphologies and quantities of BN material in PiG (phosphor in glass), the mechanical strength, heat dissipation, and luminescent properties of the sheet can be effectively controlled. PiG prepared by adding the right number of nanotubes and nanosheets has higher quantum efficiency and better heat dissipation after being excited by high power LED. Full article
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13 pages, 3684 KiB  
Communication
A Simple Method for the Synthesis of a Coral-like Boron Nitride Micro-/Nanostructure Catalyzed by Fe
by Yanjiao Li, Xueren Wang, Jian Wang, Xinfeng Wang and Dejun Zeng
Nanomaterials 2023, 13(4), 753; https://doi.org/10.3390/nano13040753 - 17 Feb 2023
Cited by 3 | Viewed by 1564
Abstract
Catalyzed by Fe, novel a coral-like boron nitride (BN) micro-/nanostructure was synthesized from B2O3 by a ball milling and annealing process. Observations of the morphology of the product indicated that the coral-like BN micro-/nanostructure consists of a bamboo-shaped nanotube stem [...] Read more.
Catalyzed by Fe, novel a coral-like boron nitride (BN) micro-/nanostructure was synthesized from B2O3 by a ball milling and annealing process. Observations of the morphology of the product indicated that the coral-like BN micro-/nanostructure consists of a bamboo-shaped nanotube stem and dense h-BN nanoflakes growing outward on the surface of the nanotube. Experimental results showed that the morphology of the BN nanotube was greatly dependent on the anneal process parameters. With the annealing time increasing from 0.5 h to 4 h, the morphology developed from smooth BN nanotubes, with a diameter size of around 100 nm, to rough, coral-like boron nitride with a large diameter of 3.6 μm. The formation mechanism of this coral-like BN micro-/nanostructure is a two-stage growth process: bamboo-shaped BN nanotubes are first generated through a vapor–liquid–solid (VLS) mechanism and then nanoflakes grow surrounding the surface of the nanotube. Acid pickling and a hydrolysis process were carried out to remove Fe, iron nitrogen and unreacted B2O3 impurities. Full article
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12 pages, 3964 KiB  
Article
Seed-Mediated Synthesis of Thin Gold Nanoplates with Tunable Edge Lengths and Optical Properties
by Zhun Qiao, Xinyu Wei, Hongpo Liu, Kai Liu and Chuanbo Gao
Nanomaterials 2023, 13(4), 711; https://doi.org/10.3390/nano13040711 - 13 Feb 2023
Cited by 1 | Viewed by 1850
Abstract
Thin Au nanoplates show intriguing localized surface plasmon resonance (LSPR) properties with potential applications in various fields. The conventional synthesis of Au nanoplates usually involves the formation of spherical nanoparticles or produces nanoplates with large thicknesses. Herein, we demonstrate a synthesis of uniform [...] Read more.
Thin Au nanoplates show intriguing localized surface plasmon resonance (LSPR) properties with potential applications in various fields. The conventional synthesis of Au nanoplates usually involves the formation of spherical nanoparticles or produces nanoplates with large thicknesses. Herein, we demonstrate a synthesis of uniform thin Au nanoplates by using Au–Ag alloy nanoframes obtained by the galvanic replacement of Ag nanoplates with HAuCl4 as the seeds and a sulfite (SO32−) as a ligand. The SO32− ligand not only complexes with the Au salt for the controlled reduction kinetics but also strongly adsorbs on Au {111} facets for effectively constraining the crystal growth on both basal sides of the Au nanoplates for controlled shape and reduced thicknesses. This seed-mediated synthesis affords Au nanoplates with a thickness of only 7.5 nm, although the thickness increases with the edge length. The edge length can be customizable in a range of 48–167 nm, leading to tunable LSPR bands in the range of 600–1000 nm. These thin Au nanoplates are applicable not only to surface-enhanced Raman spectroscopy with enhanced sensitivity and reliability but also to a broader range of LSPR-based applications. Full article
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11 pages, 4357 KiB  
Article
Construction of Nanostructured Glass-Zirconia to Improve the Interface Stability of Dental Bilayer Zirconia
by Ming Zhou, Xiaoyu Zhang, Yaming Zhang, Ding Li, Zhe Zhao, Qing Wang, Kai Tang, Lina Niu and Fu Wang
Nanomaterials 2023, 13(4), 678; https://doi.org/10.3390/nano13040678 - 9 Feb 2023
Cited by 2 | Viewed by 1521
Abstract
Bilayer zirconia restoration is one of the most commonly used restorations in dental practice, but the high frequency of the cohesive/adhesive fracture of veneered porcelain is still a problem. This paper focuses on the development of nanostructured glass-zirconia to improve the interface stability [...] Read more.
Bilayer zirconia restoration is one of the most commonly used restorations in dental practice, but the high frequency of the cohesive/adhesive fracture of veneered porcelain is still a problem. This paper focuses on the development of nanostructured glass-zirconia to improve the interface stability of dental zirconia substrate and veneered porcelain. A novel SiO2-Li2O-Al2O3 (SLA) glass was prepared and infiltrated into the surface of fully sintered dental zirconia to obtain nanostructured glass-zirconia structure. The prepared glass-zirconia was analyzed with scanning electron microscopes (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction spectroscopy (XRD). The wettability, roughness and 3D morphology of zirconia were altered, and shear bonding strength (SBS) test demonstrated almost double increase in SBS values of the nanostructured glass-zirconia structure. The failure modes and microstructure characteristics also verified the improved interfacial stability. This investigation provides a promising method for enhancing the structural stability of bilayer zirconia restorations. Full article
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17 pages, 4964 KiB  
Article
Morphological Control of Supported ZnO Nanosheet Arrays and Their Application in Photodegradation of Organic Pollutants
by Jun Wang, Bo Gao, Dongliang Liu, Lin Cheng, Yu Zhang, Dingze Lu, Huawa Yu, Aimin Chen, Shun Yuan, Kaijia Chen and Shiguang Shang
Nanomaterials 2023, 13(3), 443; https://doi.org/10.3390/nano13030443 - 21 Jan 2023
Cited by 3 | Viewed by 1502
Abstract
Supported nanostructured photocatalysis is considered to be a sustainable and promising method for water pollution photodegradation applications due to its fascinating features, including a high surface area, stability against aggregation, and easy handling and recovery. However, the preparation and morphological control of the [...] Read more.
Supported nanostructured photocatalysis is considered to be a sustainable and promising method for water pollution photodegradation applications due to its fascinating features, including a high surface area, stability against aggregation, and easy handling and recovery. However, the preparation and morphological control of the supported nanostructured photocatalyst remains a challenge. Herein, a one-step hydrothermal method is proposed to fabricate the supported vertically aligned ZnO nanosheet arrays based on aluminum foil. The morphologically controlled growth of the supported ZnO nanosheet arrays on a large scale was achieved, and the effects of hydrothermal temperature on morphologic, structural, optical, and photocatalytic properties were observed. The results reveal that the surface area and thickness of the nanosheet increase simultaneously with the increase in the hydrothermal temperature. The increase in the surface area enhances the photocatalytic activity by providing more active sites, while the increase in the thickness reduces the charge transfer and thus decreases the photocatalytic activity. The influence competition between the area increasing and thickness increasing of the ZnO nanosheet results in the nonlinear dependence between photocatalytic activity and hydrothermal temperature. By optimizing the hydrothermal growth temperature, as fabricated and supported ZnO nanosheet arrays grown at 110 °C have struck a balance between the increase in surface area and thickness, it exhibits efficient photodegradation, facile fabrication, high recyclability, and improved durability. The RhB photodegradation efficiency of optimized and grown ZnO nanosheet arrays increased by more than four times that of the unoptimized structure. With 10 cm2 of as-fabricated ZnO nanosheet arrays, the degradation ratio of 10 mg/L MO, MB, OFL, and NOR was 85%, 51%, 58%, and 71% under UV irradiation (365 nm, 20 mW/cm2) for 60 min. All the target pollutant solutions were almost completely degraded under UV irradiation for 180 min. This work offers a facile way for the fabrication and morphological control of the supported nanostructured photocatalyst with excellent photodegradation properties and has significant implications in the practical application of the supported nanostructured photocatalyst for water pollution photodegradation. Full article
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10 pages, 2675 KiB  
Article
Enhanced Tribocatalytic Degradation of Organic Pollutants by ZnO Nanoparticles of High Crystallinity
by Hua Lei, Xiaodong Cui, Xuchao Jia, Jianquan Qi, Zhu Wang and Wanping Chen
Nanomaterials 2023, 13(1), 46; https://doi.org/10.3390/nano13010046 - 22 Dec 2022
Cited by 15 | Viewed by 1601
Abstract
More and more metal oxide nanomaterials are being synthesized and investigated for degradation of organic pollutants through harvesting friction energy, yet the strategy to optimize their performance for this application has not been carefully explored up to date. In this work, three commercially [...] Read more.
More and more metal oxide nanomaterials are being synthesized and investigated for degradation of organic pollutants through harvesting friction energy, yet the strategy to optimize their performance for this application has not been carefully explored up to date. In this work, three commercially available ZnO powders are selected and compared for tribocatalytic degradation of organic dyes, among which ZnO-1 and ZnO-2 are agglomerates of spherical nanoparticles around 20 nm, and ZnO-3 are particles of high crystallinity with a regular prismatic shape and smooth surfaces, ranging from 50 to 150 nm. Compared with ZnO-1 and ZnO-2, ZnO-3 exhibits a much higher tribocatalytic degradation performance, and a high degradation rate constant of 6.566 × 10−2 min−1 is achieved for RhB, which is superior compared with previous tribocatalytic reports. The stability and universality of ZnO-3 were demonstrated through cycling tests and degradation of different types of dyes. Furthermore, the mechanism of tribocatalysis revealed that h+ was the main active species in the degradation process by ZnO. This work highlights the great significance of high crystallinity rather than a large specific surface area for the development of high-performance tribocatalysts and demonstrates the great potential of tribocatalysis for water remediation. Full article
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10 pages, 2408 KiB  
Article
Effect of Nano-Sized γ′ Phase on the Ultrasonic and Mechanical Properties of Ni-Based Superalloy
by Ziqi Jie, Zhaoning Yang, Tao Xu and Chongfeng Sun
Nanomaterials 2022, 12(23), 4162; https://doi.org/10.3390/nano12234162 - 24 Nov 2022
Viewed by 1218
Abstract
The effect of the nano-sized γ′ phase on the ultrasonic and mechanical properties of the IN939 superalloy was investigated. The results indicate that the microstructure characteristics of the nano-sized γ′ phase directly affected the ultrasonic longitudinal velocity, the attenuation coefficient, and the mechanical [...] Read more.
The effect of the nano-sized γ′ phase on the ultrasonic and mechanical properties of the IN939 superalloy was investigated. The results indicate that the microstructure characteristics of the nano-sized γ′ phase directly affected the ultrasonic longitudinal velocity, the attenuation coefficient, and the mechanical properties. The ultrasonic longitudinal velocity increased with the volume fraction of the γ′ phase, whereas the attenuation coefficient was similar to the fractional change in the γ channel width. The lower fractional change in the γ channel width, in combination with a high volume fraction of the γ′ phase, was conducive to improving the mechanical properties of the superalloy. Additionally, the variation in the ultrasonic properties could reflect the variation in the mechanical properties of the IN939 superalloy, which was beneficial for optimizing the heat treatment process and characterizing the γ′ phase precipitation behavior in a nondestructive manner. Full article
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12 pages, 4121 KiB  
Article
Lead-Free Bi0.5Na0.5TiO3 Ferroelectric Nanomaterials for Pyro-Catalytic Dye Pollutant Removal under Cold-Hot Alternation
by Zheng Wu, Siqi Wu, Siqi Hong, Xiaoyu Shi, Di Guo, Yan Zhang, Xiaoli Xu, Zhi Chen and Yanmin Jia
Nanomaterials 2022, 12(22), 4091; https://doi.org/10.3390/nano12224091 - 21 Nov 2022
Cited by 11 | Viewed by 1767
Abstract
In this work, explicitly pyro-catalytic performance is observed in sol-gel-synthesized ferroelectric Bi0.5Na0.5TiO3 lead-free nanomaterials, and its application for dye wastewater purification is also actualized under temperature fluctuations varying from 23 °C to 63 °C. The decomposition ratios of [...] Read more.
In this work, explicitly pyro-catalytic performance is observed in sol-gel-synthesized ferroelectric Bi0.5Na0.5TiO3 lead-free nanomaterials, and its application for dye wastewater purification is also actualized under temperature fluctuations varying from 23 °C to 63 °C. The decomposition ratios of the pyro-catalytic Bi0.5Na0.5TiO3 nanomaterials on Rhodamine B, methyl blue and methyl orange can reach 96.75%, 98.35% and 19.97%, respectively. In the pyro-catalytic process, the probed active species such as hydroxyl radicals, superoxide radicals and holes play an extremely important role in decomposing dye molecules. The ferroelectric Bi0.5Na0.5TiO3 lead-free nanomaterials will have an excellent prospect for dye wastewater purification due to its explicit pyro-catalysis. Full article
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7 pages, 2102 KiB  
Article
Fabrication and Performance of UV Photodetector of ZnO Nanorods Decorated with Al Nanoparticles
by Shiguang Shang, Yunpeng Dong, Wenqian Zhang and Wei Ren
Nanomaterials 2022, 12(21), 3768; https://doi.org/10.3390/nano12213768 - 26 Oct 2022
Cited by 9 | Viewed by 1477
Abstract
In this work, localized surface plasmon resonance (LSPR) mediated by aluminum nanoparticles (Al NPs) was investigated to enhance the ultraviolet (UV) response of the zinc oxide nanorods (ZnO NRs) grown by the hydrothermal method. The ZnO NRs were characterized by scanning electron microscope, [...] Read more.
In this work, localized surface plasmon resonance (LSPR) mediated by aluminum nanoparticles (Al NPs) was investigated to enhance the ultraviolet (UV) response of the zinc oxide nanorods (ZnO NRs) grown by the hydrothermal method. The ZnO NRs were characterized by scanning electron microscope, energy dispersive spectroscopy, X-ray diffractometer, Raman spectrometer, ultraviolet-visible spectrophotometer and fluorescence spectrometer. The results show that the morphology and crystalline structure of the ZnO NRs could not be changed before and after decoration with Al NPs, but the absorption rates in the UV range and the photoluminescence (PL) properties were improved. The photo-to-dark current ratio of ZnO NRs with Al NPs was about 447 for 325 nm UV light (5 mW/cm2) at 3.0 V bias, with the sensitivity increasing from 9.5 to 47.8, and the responsivity increasing from 53 to 267 mA/W. Full article
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11 pages, 3866 KiB  
Article
Template-Free Hydrothermal Synthesis of Octahedron-, Diamond-, and Plate-like ZrO2 Mono-Dispersions
by Ling Gao, Hao Zhi, Shengnan Zhang and Shifeng Liu
Nanomaterials 2022, 12(19), 3405; https://doi.org/10.3390/nano12193405 - 28 Sep 2022
Cited by 2 | Viewed by 1358
Abstract
Anisotropic ZrO2 particles with octahedron-, diamond- and plate-like morphologies are successfully synthesized by a facile hydrothermal treatment approach using NaBF4 as mineralizer. The concentration of mineralizers play a crucial role on the formation of shape-controlled ZrO2 particles thus affect the [...] Read more.
Anisotropic ZrO2 particles with octahedron-, diamond- and plate-like morphologies are successfully synthesized by a facile hydrothermal treatment approach using NaBF4 as mineralizer. The concentration of mineralizers play a crucial role on the formation of shape-controlled ZrO2 particles thus affect the particle size. With the increasing concentration of mineralizer, the crystalline sizes of the primary single-crystal and the secondary particle size both increase. With the introduction of NaBF4, F plays an essential role in tuning the crystallinity and size of primary ZrO2 nanorods along [001] direction. The synergistic effect of F and B3+ result in different epitaxial growth rate. And the secondary particles mainly crystallize on the small primary nanoparticles through the oriented attachment mechanism. The as-prepared ZrO2 particles with different sizes and shapes exhibit different photocatalytic efficiency for the degradation of organic dyes. Under UV irradiation, the highest MB degradation rate of 88% was observed within 60 min for ZrO2 photocatalyst synthesized with 0.01 mol/L NaBF4 mineralizer. Full article
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13 pages, 3012 KiB  
Article
Bimodal-Structured 0.9KNbO3-0.1BaTiO3 Solid Solutions with Highly Enhanced Electrocaloric Effect at Room Temperature
by Hongfang Zhang, Liqiang Liu, Ju Gao, K. W. Kwok, Sheng-Guo Lu, Ling-Bing Kong, Biaolin Peng and Fang Hou
Nanomaterials 2022, 12(15), 2674; https://doi.org/10.3390/nano12152674 - 4 Aug 2022
Viewed by 1284
Abstract
0.9KNbO3-0.1BaTiO3 ceramics, with a bimodal grain size distribution and typical tetragonal perovskite structure at room temperature, were prepared by using an induced abnormal grain growth (IAGG) method at a relatively low sintering temperature. In this bimodal grain size distribution structure, [...] Read more.
0.9KNbO3-0.1BaTiO3 ceramics, with a bimodal grain size distribution and typical tetragonal perovskite structure at room temperature, were prepared by using an induced abnormal grain growth (IAGG) method at a relatively low sintering temperature. In this bimodal grain size distribution structure, the extra-large grains (~10–50 μm) were evolved from the micron-sized filler powders, and the fine grains (~0.05–0.35 μm) were derived from the sol precursor matrix. The 0.9KNbO3-0.1BaTiO3 ceramics exhibit relaxor-like behavior with a diffused phase transition near room temperature, as confirmed by the presence of the polar nanodomain regions revealed through high resolution transmission electron microscope analyses. A large room-temperature electrocaloric effect (ECE) was observed, with an adiabatic temperature drop (ΔT) of 1.5 K, an isothermal entropy change (ΔS) of 2.48 J·kg−1·K−1, and high ECE strengths of |ΔT/ΔE| = 1.50 × 10−6 K·m·V−1 and ΔS/ΔE = 2.48 × 10−6 J·m·kg−1·K−1·V−1 (directly measured at E = 1.0 MV·m−1). These greatly enhanced ECEs demonstrate that our simple IAGG method is highly appreciated for synthesizing high-performance electrocaloric materials for efficient cooling devices. Full article
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12 pages, 4097 KiB  
Article
Nanostructured Superhydrophobic Titanium-Based Materials: A Novel Preparation Pathway to Attain Superhydrophobicity on TC4 Alloy
by Yuxin Wang, Jiahuan Chen, Yifan Yang, Zihan Liu, Hao Wang and Zhen He
Nanomaterials 2022, 12(12), 2086; https://doi.org/10.3390/nano12122086 - 17 Jun 2022
Cited by 13 | Viewed by 2167
Abstract
This study develops the nanostructured superhydrophobic titanium-based materials using a combined preparation method of laser marking step and the subsequent anodizing step. The structural properties were determined using an X-ray diffractometer (XRD) and scanning electron microscope (SEM), while the performance was explored by [...] Read more.
This study develops the nanostructured superhydrophobic titanium-based materials using a combined preparation method of laser marking step and the subsequent anodizing step. The structural properties were determined using an X-ray diffractometer (XRD) and scanning electron microscope (SEM), while the performance was explored by wear and corrosion tests. The laser marking caused a rough surface with paralleled grooves and protrusions, revealing surface superhydrophobicity after organic modification. The anodizing process further created a titanium oxide (TiO2) nanotube film. Both phase constituent characterization and surface elemental analysis prove the uniform nanofilm. The inert nanosized oxide film offers improved stability and superhydrophobicity. Compared to those samples only with the laser marking process, the TiO2 nanotube film enhances the corrosion resistance and mechanical stability of surface superhydrophobicity. The proposed preparation pathway serves as a novel surface engineering technique to attain a nanostructured superhydrophobic surface with other desirable performance on titanium alloys, contributing to their scale-up applications in diverse fields. Full article
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