Editorial

6 pages, 465 KiB

Open AccessEditorial

Multifunctional Nanomaterials for Energy Applications

by Simas Rackauskas, Federico Cesano and Mohammed Jasim Uddin

Nanomaterials 2022, 12(13), 2170; https://doi.org/10.3390/nano12132170 - 24 Jun 2022

Cited by 3 | Viewed by 1376

In the last few decades, global energy requirements have grown exponentially, and increased demand is expected in the upcoming decades [...] Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

Research

Jump to: Editorial, Review

11 pages, 7158 KiB

Open AccessFeature PaperArticle

Fabrication of Mn₃O₄-CeO₂-rGO as Nanocatalyst for Electro-Oxidation of Methanol

by Mohammad Bagher Askari, Seyed Mohammad Rozati and Antonio Di Bartolomeo

Nanomaterials 2022, 12(7), 1187; https://doi.org/10.3390/nano12071187 - 02 Apr 2022

Cited by 23 | Viewed by 1848

Abstract

Recently, the use of metal oxides as inexpensive and efficient catalysts has been considered by researchers. In this work, we introduce a new nanocatalyst including a mixed metal oxide, consisting of manganese oxide, cerium oxide, and reduced graphene oxide (Mn₃O₄ [...] Read more.

Recently, the use of metal oxides as inexpensive and efficient catalysts has been considered by researchers. In this work, we introduce a new nanocatalyst including a mixed metal oxide, consisting of manganese oxide, cerium oxide, and reduced graphene oxide (Mn₃O₄-CeO₂-rGO) by the hydrothermal method. The synthesized nanocatalyst was evaluated for the methanol oxidation reaction. The synergetic effect of metal oxides on the surface of rGO was investigated. Mn₃O₄-CeO₂-rGO showed an oxidation current density of 17.7 mA/cm² in overpotential of 0.51 V and 91% stability after 500 consecutive rounds of cyclic voltammetry. According to these results, the synthesized nanocatalyst can be an attractive and efficient option in the methanol oxidation reaction process. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

19 pages, 2599 KiB

Open AccessArticle

Ferric Ion Diffusion for MOF-Polymer Composite with Internal Boundary Sinks

by Kirsten I. Louw, Bronwyn H. Bradshaw-Hajek and James M. Hill

Nanomaterials 2022, 12(5), 887; https://doi.org/10.3390/nano12050887 - 07 Mar 2022

Cited by 1 | Viewed by 1365

Abstract

Simple and economical ferric ion detection is necessary in many industries. An europium-based metal organic framework has selective sensing properties for solutions containing ferric ions and shows promise as a key component in a new sensor. We study an idealised sensor that consists [...] Read more.

Simple and economical ferric ion detection is necessary in many industries. An europium-based metal organic framework has selective sensing properties for solutions containing ferric ions and shows promise as a key component in a new sensor. We study an idealised sensor that consists of metal organic framework (MOF) crystals placed on a polymer surface. A two-dimensional diffusion model is used to predict the movement of ferric ions through the solution and polymer, and the ferric ion association to a MOF crystal at the boundary between the different media. A simplified one-dimensional model identifies the choice of appropriate values for the dimensionless parameters required to optimise the time for a MOF crystal to reach steady state. The model predicts that a large non-dimensional diffusion coefficient and an effective association with a small effective flux will reduce the time to steady-state. The effective dissociation is the most significant parameter to aid the estimation of the ferric ion concentration. This paper provides some theoretical insight for material scientists to optimise the design of a new ferric ion sensor. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

12 pages, 10109 KiB

Open AccessArticle

Investigating the Interface between Ceramic Particles and Polymer Matrix in Hybrid Electrolytes by Electrochemical Strain Microscopy

by Philipp M. Veelken, Maike Wirtz, Roland Schierholz, Hermann Tempel, Hans Kungl, Rüdiger-A. Eichel and Florian Hausen

Nanomaterials 2022, 12(4), 654; https://doi.org/10.3390/nano12040654 - 15 Feb 2022

Cited by 4 | Viewed by 2067

Abstract

The interface between ceramic particles and a polymer matrix in a hybrid electrolyte is studied with high spatial resolution by means of Electrochemical Strain Microscopy (ESM), an Atomic Force Microscope (AFM)-based technique. The electrolyte consists of polyethylene oxide with lithium bis(trifluoromethanesulfonyl)imide (PEO₆ [...] Read more.

The interface between ceramic particles and a polymer matrix in a hybrid electrolyte is studied with high spatial resolution by means of Electrochemical Strain Microscopy (ESM), an Atomic Force Microscope (AFM)-based technique. The electrolyte consists of polyethylene oxide with lithium bis(trifluoromethanesulfonyl)imide (PEO₆–LiTFSI) and Li_6.5La₃Zr_1.5Ta_0.5O₁₂ (LLZO:Ta). The individual components are differentiated by their respective contact resonance, ESM amplitude and friction signals. The ESM signal shows increased amplitudes and higher contact resonance frequencies on the ceramic particles, while lower amplitudes and lower contact resonance frequencies are present on the bulk polymer phase. The amplitude distribution of the hybrid electrolyte shows a broader distribution in comparison to pure PEO₆–LiTFSI. In the direct vicinity of the particles, an interfacial area with enhanced amplitude signals is found. These results are an important contribution to elucidate the influence of the ceramic–polymer interaction on the conductivity of hybrid electrolytes. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

12 pages, 2281 KiB

Open AccessArticle

Influence of Nanoparticles and Metal Vapors on the Color of Laboratory and Atmospheric Discharges

by Victor Tarasenko, Nikita Vinogradov, Dmitry Beloplotov, Alexander Burachenko, Mikhail Lomaev and Dmitry Sorokin

Nanomaterials 2022, 12(4), 652; https://doi.org/10.3390/nano12040652 - 15 Feb 2022

Cited by 5 | Viewed by 1441

Abstract

Currently, electrical discharges occurring at altitudes of tens to hundreds of kilometers from the Earth’s surface attract considerable attention from researchers from all over the world. A significant number of (nano)particles coming from outer space burn up at these altitudes. As a result, [...] Read more.

Currently, electrical discharges occurring at altitudes of tens to hundreds of kilometers from the Earth’s surface attract considerable attention from researchers from all over the world. A significant number of (nano)particles coming from outer space burn up at these altitudes. As a result, vapors of various substances, including metals, are formed at different altitudes. This paper deals with the influence of vapors and particles released from metal electrodes on the color and shape of pulse-periodic discharge in air, nitrogen, argon, and hydrogen. It presents the results of experimental studies. The discharge was implemented under an inhomogeneous electric field and was accompanied by the generation of runaway electrons and the formation of mini-jets. It was established that regardless of the voltage pulse polarity, the electrode material significantly affects the color of spherical- and cylindrical-shaped mini jets formed when bright spots appear on electrodes. Similar jets are observed when the discharge is transformed into a spark. It was shown that the color of the plasma of mini-jets is similar to that of atmospheric discharges (red sprites, blue jets, and ghosts) at altitudes of dozens of kilometers and differs from the color of plasma of pulsed diffuse discharges in air and nitrogen at the same pressure. It was revealed that to observe the red, blue and green mini-jets, it is necessary to use aluminum, iron, and copper electrodes, respectively. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Graphical abstract

11 pages, 5168 KiB

Open AccessArticle

Aqueous Organic Zinc-Ion Hybrid Supercapacitors Prepared by 3D Vertically Aligned Graphene-Polydopamine Composite Electrode

by Ruowei Cui, Zhenwang Zhang, Huijuan Zhang, Zhihong Tang, Yuhua Xue and Guangzhi Yang

Nanomaterials 2022, 12(3), 386; https://doi.org/10.3390/nano12030386 - 25 Jan 2022

Cited by 10 | Viewed by 2623

Abstract

A three-dimensional vertical-aligned graphene-polydopamine electrode (PDA@3DVAG) composite with vertical channels and conductive network is prepared by a method of unidirectional freezing and subsequent self-polymerization. When the prepared PDA@3DVAG is constructed as the positive electrode of zinc-ion hybrid supercapacitors (ZHSCs), excellent electrochemical performances are [...] Read more.

A three-dimensional vertical-aligned graphene-polydopamine electrode (PDA@3DVAG) composite with vertical channels and conductive network is prepared by a method of unidirectional freezing and subsequent self-polymerization. When the prepared PDA@3DVAG is constructed as the positive electrode of zinc-ion hybrid supercapacitors (ZHSCs), excellent electrochemical performances are obtained. Compared with the conventional electrolyte, PDA@3DVAG composite electrode in highly concentrated salt electrolyte exhibits better multiplicity performance (48.92% at a current density of 3 A g⁻¹), wider voltage window (−0.8~0.8 V), better cycle performance with specific capacitance from 96.7 to 59.8 F g⁻¹, and higher energy density (46.14 Wh kg⁻¹). Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

23 pages, 10118 KiB

Open AccessFeature PaperArticle

The Key Role of Tin (Sn) in Microstructure and Mechanical Properties of Ti₂SnC (M₂AX) Thin Nanocrystalline Films and Powdered Polycrystalline Samples

by Snejana Bakardjieva, Jiří Plocek, Bauyrzhan Ismagulov, Jaroslav Kupčík, Jiří Vacík, Giovanni Ceccio, Vasily Lavrentiev, Jiří Němeček, Štefan Michna and Robert Klie

Nanomaterials 2022, 12(3), 307; https://doi.org/10.3390/nano12030307 - 18 Jan 2022

Cited by 3 | Viewed by 1866

Abstract

Layered ternary Ti₂SnC carbides have attracted significant attention because of their advantage as a M2AX phase to bridge the gap between properties of metals and ceramics. In this study, Ti₂SnC materials were synthesized by two different methods—an unconventional low-energy [...] Read more.

Layered ternary Ti₂SnC carbides have attracted significant attention because of their advantage as a M2AX phase to bridge the gap between properties of metals and ceramics. In this study, Ti₂SnC materials were synthesized by two different methods—an unconventional low-energy ion facility (LEIF) based on Ar⁺ ion beam sputtering of the Ti, Sn, and C targets and sintering of a compressed mixture consisting of Ti, Sn, and C elemental powders up to 1250 °C. The Ti₂SnC nanocrystalline thin films obtained by LEIF were irradiated by Ar⁺ ions with an energy of 30 keV to the fluence of 1.10¹⁵ cm⁻² in order to examine their irradiation-induced resistivity. Quantitative structural analysis obtained by Cs-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) confirmed transition from ternary Ti₂SnC to binary Ti_0.98C carbide due to irradiation-induced β-Sn surface segregation. The nanoindentation of Ti₂SnC thin nanocrystalline films and Ti₂SnC polycrystalline powders shows that irradiation did not affect significantly their mechanical properties when concerning their hardness (H) and Young’s modulus (E). We highlighted the importance of the HAADF-STEM techniques to track atomic pathways clarifying the behavior of Sn atoms at the proximity of irradiation-induced nanoscale defects in Ti₂SnC thin films. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Graphical abstract

14 pages, 3209 KiB

Open AccessArticle

Sustainable and Printable Nanocellulose-Based Ionogels as Gel Polymer Electrolytes for Supercapacitors

by Rosa M. González-Gil, Mateu Borràs, Aiman Chbani, Tiffany Abitbol, Andreas Fall, Christian Aulin, Christophe Aucher and Sandra Martínez-Crespiera

Nanomaterials 2022, 12(2), 273; https://doi.org/10.3390/nano12020273 - 15 Jan 2022

Cited by 6 | Viewed by 2969

Abstract

A new gel polymer electrolyte (GPE) based supercapacitor with an ionic conductivity up to 0.32–0.94 mS cm⁻² has been synthesized from a mixture of an ionic liquid (IL) with nanocellulose (NC). The new NC-ionogel was prepared by combining the IL 1-ethyl-3-methylimidazolium dimethyl [...] Read more.

A new gel polymer electrolyte (GPE) based supercapacitor with an ionic conductivity up to 0.32–0.94 mS cm⁻² has been synthesized from a mixture of an ionic liquid (IL) with nanocellulose (NC). The new NC-ionogel was prepared by combining the IL 1-ethyl-3-methylimidazolium dimethyl phosphate (EMIMP) with carboxymethylated cellulose nanofibers (CNFc) at different ratios (CNFc ratio from 1 to 4). The addition of CNFc improved the ionogel properties to become easily printable onto the electrode surface. The new GPE based supercapacitor cell showed good electrochemical performance with specific capacitance of 160 F g⁻¹ and an equivalent series resistance (ESR) of 10.2 Ω cm⁻² at a current density of 1 mA cm⁻². The accessibility to the full capacitance of the device is demonstrated after the addition of CNFc in EMIMP compared to the pristine EMIMP (99 F g⁻¹ and 14.7 Ω cm⁻²). Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

16 pages, 2564 KiB

Open AccessCommunication

Luminescence of SiO₂-BaF₂:Tb³⁺, Eu³⁺ Nano-Glass-Ceramics Made from Sol–Gel Method at Low Temperature

by Natalia Pawlik, Barbara Szpikowska-Sroka, Tomasz Goryczka, Ewa Pietrasik and Wojciech A. Pisarski

Nanomaterials 2022, 12(2), 259; https://doi.org/10.3390/nano12020259 - 14 Jan 2022

Cited by 8 | Viewed by 1864

Abstract

The synthesis and characterization of multicolor light-emitting nanomaterials based on rare earths (RE³⁺) are of great importance due to their possible use in optoelectronic devices, such as LEDs or displays. In the present work, oxyfluoride glass-ceramics containing BaF₂ nanocrystals co-doped [...] Read more.

The synthesis and characterization of multicolor light-emitting nanomaterials based on rare earths (RE³⁺) are of great importance due to their possible use in optoelectronic devices, such as LEDs or displays. In the present work, oxyfluoride glass-ceramics containing BaF₂ nanocrystals co-doped with Tb³⁺, Eu³⁺ ions were fabricated from amorphous xerogels at 350 °C. The analysis of the thermal behavior of fabricated xerogels was performed using TG/DSC measurements (thermogravimetry (TG), differential scanning calorimetry (DSC)). The crystallization of BaF₂ phase at the nanoscale was confirmed by X-ray diffraction (XRD) measurements and transmission electron microscopy (TEM), and the changes in silicate sol–gel host were determined by attenuated total reflectance infrared (ATR-IR) spectroscopy. The luminescent characterization of prepared sol–gel materials was carried out by excitation and emission spectra along with decay analysis from the ⁵D₄ level of Tb³⁺. As a result, the visible light according to the electronic transitions of Tb³⁺ (⁵D₄ → ⁷F_J (J = 6–3)) and Eu³⁺ (⁵D₀ → ⁷F_J (J = 0–4)) was recorded. It was also observed that co-doping with Eu³⁺ caused the shortening in decay times of the ⁵D₄ state from 1.11 ms to 0.88 ms (for xerogels) and from 6.56 ms to 4.06 ms (for glass-ceramics). Thus, based on lifetime values, the Tb³⁺/Eu³⁺ energy transfer (ET) efficiencies were estimated to be almost 21% for xerogels and 38% for nano-glass-ceramics. Therefore, such materials could be successfully predisposed for laser technologies, spectral converters, and three-dimensional displays. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

17 pages, 3004 KiB

Open AccessArticle

On the Use of Carbon Cables from Plastic Solvent Combinations of Polystyrene and Toluene in Carbon Nanotube Synthesis

by Alvin Orbaek White, Ali Hedayati, Tim Yick, Varun Shenoy Gangoli, Yubiao Niu, Sean Lethbridge, Ioannis Tsampanakis, Gemma Swan, Léo Pointeaux, Abigail Crane, Rhys Charles, Jainaba Sallah-Conteh, Andrew O. Anderson, Matthew Lloyd Davies, Stuart. J. Corr and Richard E. Palmer

Nanomaterials 2022, 12(1), 9; https://doi.org/10.3390/nano12010009 - 21 Dec 2021

Cited by 11 | Viewed by 4748

Abstract

For every three people on the planet, there are approximately two Tonnes (Te) of plastic waste. We show that carbon recovery from polystyrene (PS) plastic is enhanced by the coaddition of solvents to grow carbon nanotubes (CNTs) by liquid injection chemical vapour deposition. [...] Read more.

For every three people on the planet, there are approximately two Tonnes (Te) of plastic waste. We show that carbon recovery from polystyrene (PS) plastic is enhanced by the coaddition of solvents to grow carbon nanotubes (CNTs) by liquid injection chemical vapour deposition. Polystyrene was loaded up to 4 wt% in toluene and heated to 780 °C in the presence of a ferrocene catalyst and a hydrogen/argon carrier gas at a 1:19 ratio. High resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Raman spectroscopy were used to identify multiwalled carbon nanotubes (MWCNTs). The PS addition in the range from 0 to 4 wt% showed improved quality and CNT homogeneity; Raman “Graphitic/Defective” (G/D) values increased from 1.9 to 2.3; mean CNT diameters increased from 43.0 to 49.2 nm; and maximum CNT yield increased from 11.37% to 14.31%. Since both the CNT diameters and the percentage yield increased following the addition of polystyrene, we conclude that carbon from PS contributes to the carbon within the MWCNTs. The electrical contact resistance of acid-washed Bucky papers produced from each loading ranged from 2.2 to 4.4 Ohm, with no direct correlation to PS loading. Due to this narrow range, materials with different loadings were mixed to create the six wires of an Ethernet cable and tested using iPerf3; the cable achieved up- and down- link speeds of ~99.5 Mbps, i.e., comparable to Cu wire with the same dimensions (~99.5 Mbps). The lifecycle assessment (LCA) of CNT wire production was compared to copper wire production for a use case in a Boeing 747-400 over the lifespan of the aircraft. Due to their lightweight nature, the CNT wires decreased the CO₂ footprint by 21 kTonnes (kTe) over the aircraft’s lifespan. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Graphical abstract

12 pages, 3022 KiB

Open AccessArticle

Tailoring Amine-Functionalized Ti-MOFs via a Mixed Ligands Strategy for High-Efficiency CO₂ Capture

by Yinji Wan, Yefan Miao, Tianjie Qiu, Dekai Kong, Yingxiao Wu, Qiuning Zhang, Jinming Shi, Ruiqin Zhong and Ruqiang Zou

Nanomaterials 2021, 11(12), 3348; https://doi.org/10.3390/nano11123348 - 10 Dec 2021

Cited by 10 | Viewed by 3264

Abstract

Amine-functionalized metal-organic frameworks (MOFs) are a promising strategy for the high-efficiency capture and separation of CO₂. In this work, by tuning the ratio of 1,3,5-benzenetricarboxylic acid (H₃BTC) to 5-aminoisophthalic acid (5-NH₂-H₂IPA), we designed and synthesized [...] Read more.

Amine-functionalized metal-organic frameworks (MOFs) are a promising strategy for the high-efficiency capture and separation of CO₂. In this work, by tuning the ratio of 1,3,5-benzenetricarboxylic acid (H₃BTC) to 5-aminoisophthalic acid (5-NH₂-H₂IPA), we designed and synthesized a series of amine-functionalized highly stable Ti-based MOFs (named MIP-207-NH₂-n, in which n represents 15%, 25%, 50%, 60%, and 100%). The structural analysis shows that the original framework of MIP-207 in the MIP-207-NH₂-n (n = 15%, 25%, and 50%) MOFs remains intact when the mole ratio of ligand H₃BTC to 5-NH₂-H₂IPA is less than 1 to 1 in the resulting MOFs. By the introduction of amino groups, MIP-207-NH₂-25% demonstrates outstanding CO₂ capture performance up to 3.96 and 2.91 mmol g⁻¹, 20.7% and 43.3% higher than those of unmodified MIP-207 at 0 and 25 °C, respectively. Furthermore, the breakthrough experiment indicates that the dynamic CO₂ adsorption capacity and CO₂/N₂ separation factors of MIP-207-NH₂-25% are increased by about 25% and 15%, respectively. This work provides an additional strategy to construct amine-functionalized MOFs with the maintenance of the original MOF structure and high performance of CO₂ capture and separation. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

15 pages, 5824 KiB

Open AccessArticle

Catalytic Hydrogen Evolution of NaBH₄ Hydrolysis by Cobalt Nanoparticles Supported on Bagasse-Derived Porous Carbon

by Yiting Bu, Jiaxi Liu, Hailiang Chu, Sheng Wei, Qingqing Yin, Li Kang, Xiaoshuang Luo, Lixian Sun, Fen Xu, Pengru Huang, Federico Rosei, Aleskey A. Pimerzin, Hans Juergen Seifert, Yong Du and Jianchuan Wang

Nanomaterials 2021, 11(12), 3259; https://doi.org/10.3390/nano11123259 - 30 Nov 2021

Cited by 21 | Viewed by 2891

Abstract

As a promising hydrogen storage material, sodium borohydride (NaBH₄) exhibits superior stability in alkaline solutions and delivers 10.8 wt.% theoretical hydrogen storage capacity. Nevertheless, its hydrolysis reaction at room temperature must be activated and accelerated by adding an effective catalyst. In [...] Read more.

As a promising hydrogen storage material, sodium borohydride (NaBH₄) exhibits superior stability in alkaline solutions and delivers 10.8 wt.% theoretical hydrogen storage capacity. Nevertheless, its hydrolysis reaction at room temperature must be activated and accelerated by adding an effective catalyst. In this study, we synthesize Co nanoparticles supported on bagasse-derived porous carbon (Co@xPC) for catalytic hydrolytic dehydrogenation of NaBH₄. According to the experimental results, Co nanoparticles with uniform particle size and high dispersion are successfully supported on porous carbon to achieve a Co@150PC catalyst. It exhibits particularly high activity of hydrogen generation with the optimal hydrogen production rate of 11086.4 mL_H2∙min⁻¹∙g_Co⁻¹ and low activation energy (E_a) of 31.25 kJ mol⁻¹. The calculation results based on density functional theory (DFT) indicate that the Co@xPC structure is conducive to the dissociation of [BH₄]⁻, which effectively enhances the hydrolysis efficiency of NaBH₄. Moreover, Co@150PC presents an excellent durability, retaining 72.0% of the initial catalyst activity after 15 cycling tests. Moreover, we also explored the degradation mechanism of catalyst performance. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

15 pages, 4154 KiB

Open AccessArticle

An Effective Method to Accurately Extract the Parameters of Single Diode Model of Solar Cells

by Zhaoxu Song, Kun Fang, Xiaofang Sun, Ying Liang, Wei Lin, Chuanzhong Xu, Gongyi Huang and Fei Yu

Nanomaterials 2021, 11(10), 2615; https://doi.org/10.3390/nano11102615 - 04 Oct 2021

Cited by 10 | Viewed by 1755

Abstract

A non-iterative method is presented to accurately extract the five parameters of single diode model of solar cells in this paper. This method overcomes the problems of complexity and accuracy by simplifying the calculation process. Key parts of the equation are to be [...] Read more.

A non-iterative method is presented to accurately extract the five parameters of single diode model of solar cells in this paper. This method overcomes the problems of complexity and accuracy by simplifying the calculation process. Key parts of the equation are to be adjusted dynamically so that the desired five parameters can be obtained from the I-V curve. Then, the I-V and P-V characteristic curves of solar cells are used to compare the effectiveness of this method with other methods. Furthermore, the root mean square error analysis shows that this method is more applicable than other methods. Finally, the I-V and P-V characteristics simulated by using the extracted parameters in this method are compared and discussed with the experimental data of solar cells under different conditions. In fact, this extraction process can be regarded as an effective and accurate method to estimate solar cells’ single diode model parameters. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

17 pages, 37615 KiB

Open AccessEditor’s ChoiceArticle

Flexible Layered-Graphene Charge Modulation for Highly Stable Triboelectric Nanogenerator

by Mamina Sahoo, Sz-Nian Lai, Jyh-Ming Wu, Ming-Chung Wu and Chao-Sung Lai

Nanomaterials 2021, 11(9), 2276; https://doi.org/10.3390/nano11092276 - 01 Sep 2021

Cited by 13 | Viewed by 3233

Abstract

The continuous quest to enhance the output performance of triboelectric nanogenerators (TENGs) based on the surface charge density of the tribolayer has motivated researchers to harvest mechanical energy efficiently. Most of the previous work focused on the enhancement of negative triboelectric charges. The [...] Read more.

The continuous quest to enhance the output performance of triboelectric nanogenerators (TENGs) based on the surface charge density of the tribolayer has motivated researchers to harvest mechanical energy efficiently. Most of the previous work focused on the enhancement of negative triboelectric charges. The enhancement of charge density over positive tribolayer has been less investigated. In this work, we developed a layer-by-layer assembled multilayer graphene-based TENG to enhance the charge density by creatively introducing a charge trapping layer (CTL) Al₂O₃ in between the positive triboelectric layer and conducting electrode to construct an attractive flexible TENG. Based on the experimental results, the optimized three layers of graphene TENG (3L-Gr-TENG) with CTL showed a 30-fold enhancement in output power compared to its counterpart, 3L-Gr-TENG without CTL. This remarkably enhanced performance can be ascribed to the synergistic effect between the optimized graphene layers with high dielectric CTL. Moreover, the device exhibited outstanding stability after continuous operation of >2000 cycles. Additionally, the device was capable of powering 20 green LEDs and sufficient to power an electronic timer with rectifying circuits. This research provides a new insight to improve the charge density of Gr-TENGs as energy harvesters for next-generation flexible electronics. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Graphical abstract

17 pages, 8325 KiB

Open AccessEditor’s ChoiceArticle

Li₄(OH)₃Br-Based Shape Stabilized Composites for High-Temperature TES Applications: Selection of the Most Convenient Supporting Material

by Imane Mahroug, Stefania Doppiu, Jean-Luc Dauvergne, Angel Serrano and Elena Palomo del Barrio

Nanomaterials 2021, 11(5), 1279; https://doi.org/10.3390/nano11051279 - 13 May 2021

Cited by 4 | Viewed by 1893

Abstract

Peritectic compound Li₄(OH)₃Br has been recently proposed as phase change material (PCM) for thermal energy storage (TES) applications at approx. 300 °C Compared to competitor PCM materials (e.g., sodium nitrate), the main assets of this compound are high volumetric [...] Read more.

Peritectic compound Li₄(OH)₃Br has been recently proposed as phase change material (PCM) for thermal energy storage (TES) applications at approx. 300 °C Compared to competitor PCM materials (e.g., sodium nitrate), the main assets of this compound are high volumetric latent heat storage capacity (>140 kWh/m³) and very low volume changes (<3%) during peritectic reaction and melting. The objective of the present work was to find proper supporting materials able to shape stabilize Li₄(OH)₃Br during the formation of the melt and after its complete melting, avoiding any leakage and thus obtaining a composite apparently always in the solid state during the charge and discharge of the TES material. Micro-nanoparticles of MgO, Fe₂O₃, CuO, SiO₂ and Al₂O₃ have been considered as candidate supporting materials combined with the cold-compression route for shape-stabilized composites preparation. The work carried out allowed for the identification of the most promising composite based on MgO nanoparticles through a deep experimental analysis and characterization, including chemical compatibility tests, anti-leakage performance evaluation, structural and thermodynamic properties analysis and preliminary cycling stability study. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

Review

Jump to: Editorial, Research

25 pages, 9304 KiB

Open AccessReview

Cellulose Nanocrystals (CNC)-Based Functional Materials for Supercapacitor Applications

by Arulppan Durairaj, Moorthy Maruthapandi, Arumugam Saravanan, John H. T. Luong and Aharon Gedanken

Nanomaterials 2022, 12(11), 1828; https://doi.org/10.3390/nano12111828 - 26 May 2022

Cited by 14 | Viewed by 3544

Abstract

The growth of industrialization and the population has increased the usage of fossil fuels, resulting in the emission of large amounts of CO_2. This serious environmental issue can be abated by using sustainable and environmentally friendly materials with promising novel and superior [...] Read more.

The growth of industrialization and the population has increased the usage of fossil fuels, resulting in the emission of large amounts of CO_2. This serious environmental issue can be abated by using sustainable and environmentally friendly materials with promising novel and superior performance as an alternative to petroleum-based plastics. Emerging nanomaterials derived from abundant natural resources have received considerable attention as candidates to replace petroleum-based synthetic polymers. As renewable materials from biomass, cellulose nanocrystals (CNCs) nanomaterials exhibit unique physicochemical properties, low cost, biocompatibility and biodegradability. Among a plethora of applications, CNCs have become proven nanomaterials for energy applications encompassing energy storage devices and supercapacitors. This review highlights the recent research contribution on novel CNC-conductive materials and CNCs-based nanocomposites, focusing on their synthesis, surface functionalization and potential applications as supercapacitors (SCs). The synthesis of CNCs encompasses various pretreatment steps including acid hydrolysis, mechanical exfoliation and enzymatic and combination processes from renewable carbon sources. For the widespread applications of CNCs, their derivatives such as carboxylated CNCs, aldehyde-CNCs, hydride-CNCs and sulfonated CNC-based materials are more pertinent. The potential applications of CNCs-conductive hybrid composites as SCs, critical technical issues and the future feasibility of this endeavor are highlighted. Discussion is also extended to the transformation of renewable and low-attractive CNCs to conductive nanocomposites using green approaches. This review also addresses the key scientific achievements and industrial uses of nanoscale materials and composites for energy conversion and storage applications. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Graphical abstract

38 pages, 14889 KiB

Open AccessReview

Colloidal Lithography for Photovoltaics: An Attractive Route for Light Management

by Rui D. Oliveira, Ana Mouquinho, Pedro Centeno, Miguel Alexandre, Sirazul Haque, Rodrigo Martins, Elvira Fortunato, Hugo Águas and Manuel J. Mendes

Nanomaterials 2021, 11(7), 1665; https://doi.org/10.3390/nano11071665 - 24 Jun 2021

Cited by 20 | Viewed by 5316

Abstract

The pursuit of ever-more efficient, reliable, and affordable solar cells has pushed the development of nano/micro-technological solutions capable of boosting photovoltaic (PV) performance without significantly increasing costs. One of the most relevant solutions is based on light management via photonic wavelength-sized structures, as [...] Read more.

The pursuit of ever-more efficient, reliable, and affordable solar cells has pushed the development of nano/micro-technological solutions capable of boosting photovoltaic (PV) performance without significantly increasing costs. One of the most relevant solutions is based on light management via photonic wavelength-sized structures, as these enable pronounced efficiency improvements by reducing reflection and by trapping the light inside the devices. Furthermore, optimized microstructured coatings allow self-cleaning functionality via effective water repulsion, which reduces the accumulation of dust and particles that cause shading. Nevertheless, when it comes to market deployment, nano/micro-patterning strategies can only find application in the PV industry if their integration does not require high additional costs or delays in high-throughput solar cell manufacturing. As such, colloidal lithography (CL) is considered the preferential structuring method for PV, as it is an inexpensive and highly scalable soft-patterning technique allowing nanoscopic precision over indefinitely large areas. Tuning specific parameters, such as the size of colloids, shape, monodispersity, and final arrangement, CL enables the production of various templates/masks for different purposes and applications. This review intends to compile several recent high-profile works on this subject and how they can influence the future of solar electricity. Full article

(This article belongs to the Special Issue Multifunctional Nanomaterials for Energy Applications)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Multifunctional Nanomaterials for Energy Applications

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (17 papers)

Editorial

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI