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Thummavichai K, Nguyen THQ, Longo G, Qiang D, Zoppi G, Schlettwein D, Maiello P, Fleck N, Wang N, Zhu Y. Effect of metal dopants on the electrochromic performance of hydrothermally-prepared tungsten oxide materials. RSC Adv 2023; 13:35457-35467. [PMID: 38115985 PMCID: PMC10728781 DOI: 10.1039/d3ra06018g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 11/13/2023] [Indexed: 12/21/2023] Open
Abstract
Electrochromic (EC) glass has the potential to significantly improve energy efficiency in buildings by controlling the amount of light and heat that the building exchanges with its exterior. However, the development of EC materials is still hindered by key challenges such as slow switching time, low coloration efficiency, short cycling lifetime, and material degradation. Metal doping is a promising technique to enhance the performance of metal oxide-based EC materials, where adding a small amount of metal into the host material can lead to lattice distortion, a variation of oxygen vacancies, and a shorter ion transfer path during the insertion and de-insertion process. In this study, we investigated the effects of niobium, gadolinium, and erbium doping on tungsten oxide using a single-step solvothermal technique. Our results demonstrate that both insertion and de-insertion current density of a doped sample can be significantly enhanced by metal elements, with an improvement of about 5, 4 and 3.5 times for niobium, gadolinium and erbium doped tungsten oxide, respectively compared to a pure tungsten oxide sample. Moreover, the colouration efficiency increased by 16, 9 and 24% when doping with niobium, gadolinium and erbium, respectively. These findings suggest that metal doping is a promising technique for improving the performance of EC materials and can pave the way for the development of more efficient EC glass for building applications.
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Affiliation(s)
- Kunyapat Thummavichai
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University NE1 8ST Newcastle UK
| | - Thi Hai Quyen Nguyen
- Institute of Applied Physics, Center for Materials Research (ZfM/LaMa), Justus-Liebig University 35392 Giessen Germany
| | - Giulia Longo
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University NE1 8ST Newcastle UK
| | - Dayuan Qiang
- School of Mechanical Engineering Sciences, University of Surrey GU2 7XH Surrey UK
| | - Guillaume Zoppi
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University NE1 8ST Newcastle UK
| | - Derck Schlettwein
- Institute of Applied Physics, Center for Materials Research (ZfM/LaMa), Justus-Liebig University 35392 Giessen Germany
| | - Pietro Maiello
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University NE1 8ST Newcastle UK
| | - Nicole Fleck
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University NE1 8ST Newcastle UK
| | - Nannan Wang
- State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, School of Resources, Environment and Materials, Guangxi University 530004 Nanning China
| | - Yanqiu Zhu
- College of Engineering, Mathematics and Physical Sciences, University of Exeter EX4 4QF Exeter UK
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2
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Liu H, Wang Y, Wang H, Xie H, Li Y, Zou P, Zeng J, Liang T, Qi X. Surface modification of rare earth Sm-doped WO 3 films through polydopamine for enhanced electrochromic energy storage performance. J Colloid Interface Sci 2023; 649:510-518. [PMID: 37356152 DOI: 10.1016/j.jcis.2023.06.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 06/04/2023] [Accepted: 06/14/2023] [Indexed: 06/27/2023]
Abstract
Electrochromic materials (ECMs) could exhibit reversible color changes upon application of the external electric field, which exhibits huge application prospects in smart windows, energy storage devices, and displays. For the practical application of ECMs, the fast response speed and long cyclic stability are urgent. In this work, the nanoporous Sm-doped WO3 (WSm) films were constructed using hydrothermal technology, then polydopamine (PDA) was modified on the surface of WSm film to obtain the WSm/Px (x = 0.25, 0.5, 1.0, and 2.0) hybrid films. WSm/Px hybrid films displayed high optical contrast and large areal capacitance. In addition, in comparison with WSm film, the WSm/Px hybrid films exhibited faster response speed and better cyclic stability because PDA film enhanced the interface ion transport ability and electrochemical structural stability of the nanoporous WSm film. Notably, the WSm/P1.0 hybrid film displayed the colored/bleached times of 7.4/2.9 s, retained 90.2% of the primitive optical contrast (68.5%) after 5000 electrochromic cycles. Furthermore, the areal capacitance of WSm film could be increased by 224% through the modification of the PDA. Therefore, WSm/Px hybrid films are great prospects for electrochromic energy-saving and storage windows.
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Affiliation(s)
- Haitao Liu
- Engineering Research Center for Hydrogen Energy Materials and Devices, College of Rare Earths, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China; Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China
| | - Yongxiang Wang
- Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China
| | - Hengyu Wang
- Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China
| | - Haolin Xie
- Engineering Research Center for Hydrogen Energy Materials and Devices, College of Rare Earths, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China
| | - Yinghan Li
- Engineering Research Center for Hydrogen Energy Materials and Devices, College of Rare Earths, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China
| | - Peng Zou
- Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China
| | - Jinming Zeng
- Engineering Research Center for Hydrogen Energy Materials and Devices, College of Rare Earths, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China.
| | - Tongxiang Liang
- Engineering Research Center for Hydrogen Energy Materials and Devices, College of Rare Earths, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China
| | - Xiaopeng Qi
- Engineering Research Center for Hydrogen Energy Materials and Devices, College of Rare Earths, Jiangxi University of Science and Technology, 86 Hong Qi Road, Ganzhou 341000, PR China.
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3
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Zhu L, Meng Z, Hu S, Zhao T, Zhao B. Understanding Metal-Semiconductor Plasmonic Resonance Coupling through Surface-Enhanced Raman Scattering. ACS APPLIED MATERIALS & INTERFACES 2023; 15:22730-22736. [PMID: 37125659 DOI: 10.1021/acsami.3c02160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Although there has been intense research on plasmon-induced charge transfer within metal/semiconductor heterostructures, previous studies have all focused on the surface plasmonic resonance (SPR) of only noble metals. Herein and for the first time, we observe and take into account the plasmonic coupling between SPR of both noble-metal and semiconductor nanostructures. A W18O49/Ag heterostructure composed of metallic Ag nanoparticles (Ag NPs) and semiconducting W18O49 nanowires (W18O49 NWs) is designed and fabricated, which exhibits a broad and strong SPR absorption in the visible wavelength range. This SPR band is attributed to the SPR coupling between the SPR of both Ag NPs and W18O49 NWs. Surface-enhanced Raman scattering (SERS) is then used to reveal the interactions between the metal SPR, semiconductor SPR, and the heterostructure's charge transfer (CT) process, demonstrating that such coupled SPR enhanced the heterostructure's internal CT and SERS signals. Finally, we proposed a new coupled-plasmon-induced charge transfer mechanism to interpret the improved CT efficiency between the SERS substrate and molecules. Our work provides insight for further studies on plasmonic effects and interfacial charge transfer in metal/semiconductor heterostructures.
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Affiliation(s)
- Lin Zhu
- Stake Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, People's Republic of China
| | - Zhen Meng
- Stake Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, People's Republic of China
| | - Saizhen Hu
- Stake Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, People's Republic of China
| | - Tiancong Zhao
- Department of Chemistry and Laboratory of Advanced Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers, Collaborative Innovation Center of Chemistry for Energy Materials (2011-iChEM), College of Chemistry and Materials, Fudan University, Shanghai 200433, People's Republic of China
| | - Bing Zhao
- Stake Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, People's Republic of China
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4
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Habtamu A, Ujihara M. The mechanism of water pollutant photodegradation by mixed and core-shell WO 3/TiO 2 nanocomposites. RSC Adv 2023; 13:12926-12940. [PMID: 37114017 PMCID: PMC10128107 DOI: 10.1039/d3ra01582c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Environmental pollution is one of the biggest concerns in the world today, and solar energy-driven photocatalysis is a promising method for decomposing pollutants in aqueous systems. In this study, the photocatalytic efficiency and catalytic mechanism of WO3-loaded TiO2 nanocomposites of various structures were analyzed. The nanocomposites were synthesized via sol-gel reactions using mixtures of precursors at various ratios (5%, 8%, and 10 wt% WO3 in the nanocomposites) and via core-shell approaches (TiO2@WO3 and WO3@TiO2 in a 9 : 1 ratio of TiO2 : WO3). After calcination at 450 °C, the nanocomposites were characterized and used as photocatalysts. The kinetics of photocatalysis with these nanocomposites for the degradation of methylene blue (MB+) and methyl orange (MO-) under UV light (365 nm) were analyzed as pseudo-first-order reactions. The decomposition rate of MB+ was much higher than that of MO-, and the adsorption behavior of the dyes in the dark suggested that the negatively charged surface of WO3 played an important role in adsorbing the cationic dye. Scavengers were used to quench the active species (superoxide, hole, and hydroxyl radicals), and the results indicated that hydroxyl radicals were the most active species; however, the active species were generated more evenly on the mixed surfaces of WO3 and TiO2 than on the core-shell structures. This finding shows that the photoreaction mechanisms could be controlled through adjustments to the nanocomposite structure. These results can guide the design and preparation of photocatalysts with improved and controlled activities for environmental remediation.
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Affiliation(s)
- Abdisa Habtamu
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology 43 Keelung Road 10607 Taipei Taiwan
| | - Masaki Ujihara
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology 43 Keelung Road 10607 Taipei Taiwan
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Ortiz J, Acosta D, Magaña C. Long-term cycling and stability of crystalline WO3 electrochromic thin films prepared by spray pyrolysis. J Solid State Electrochem 2022. [DOI: 10.1007/s10008-022-05211-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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6
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Chen PR, Fu HW, Yang SM, Lu KC. Chemical Vapor Deposition-Fabricated Manganese-Doped and Potassium-Doped Hexagonal Tungsten Trioxide Nanowires with Enhanced Gas Sensing and Photocatalytic Properties. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1208. [PMID: 35407326 PMCID: PMC9002994 DOI: 10.3390/nano12071208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/14/2022] [Accepted: 04/01/2022] [Indexed: 02/01/2023]
Abstract
Owing to its unique and variable lattice structure and stoichiometric ratio, tungsten oxide is suitable for material modification; for example, doping is expected to improve its catalytic properties. However, most of the doping experiments are conducted by hydrothermal or multi-step synthesis, which is not only time-consuming but also prone to solvent contamination, having little room for mass production. Here, without a catalyst, we report the formation of high-crystallinity manganese-doped and potassium-doped tungsten oxide nanowires through chemical vapor deposition (CVD) with interesting characterization, photocatalytic, and gas sensing properties. The structure and composition of the nanowires were characterized by transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS), respectively, while the morphology and chemical valence were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. Electrical measurements showed that the single nanowires doped with manganese and potassium had resistivities of 1.81 × 0-5 Ω·m and 1.93 × 10-5 Ω·m, respectively. The doping contributed to the phase transition from monoclinic to metastable hexagonal for the tungsten oxide nanowires, the structure of which is known for its hexagonal electron channels. The hexagonal structure provided efficient charge transfer and enhanced the catalytic efficiency of the tungsten oxide nanowires, resulting in a catalytic efficiency of 98.5% for the manganese-doped tungsten oxide nanowires and 97.73% for the potassium-doped tungsten oxide nanowires after four hours of degradation of methylene blue. Additionally, the gas sensing response for 20 ppm of ethanol showed a positive dependence of doping with the manganese-doped and potassium-doped responses being 14.4% and 29.7%, respectively, higher than the pure response at 250 °C. The manganese-doped and potassium-doped tungsten oxide nanowires are attractive candidates in gas sensing, photocatalytic, and energy storage applications, including water splitting, photochromism, and rechargeable batteries.
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Affiliation(s)
- Pin-Ru Chen
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan; (P.-R.C.); (H.-W.F.); (S.-M.Y.)
| | - Hsuan-Wei Fu
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan; (P.-R.C.); (H.-W.F.); (S.-M.Y.)
| | - Shu-Meng Yang
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan; (P.-R.C.); (H.-W.F.); (S.-M.Y.)
| | - Kuo-Chang Lu
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan; (P.-R.C.); (H.-W.F.); (S.-M.Y.)
- Core Facility Center, National Cheng Kung University, Tainan 701, Taiwan
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Wang Y, Shen G, Tang T, Zeng J, Sagar RUR, Qi X, Liang T. Construction of doped-rare earth (Ce, Eu, Sm, Gd) WO3 porous nanofilm for superior electrochromic and energy storage windows. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.140099] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Pinedo-Escobar JA, Fan J, Moctezuma E, Gomez-Solís C, Carrillo Martinez CJ, Gracia-Espino E. Nanoparticulate Double-Heterojunction Photocatalysts Comprising TiO 2(Anatase)/WO 3/TiO 2(Rutile) with Enhanced Photocatalytic Activity toward the Degradation of Methyl Orange under Near-Ultraviolet and Visible Light. ACS OMEGA 2021; 6:11840-11848. [PMID: 34056338 PMCID: PMC8154020 DOI: 10.1021/acsomega.0c06054] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 04/21/2021] [Indexed: 05/14/2023]
Abstract
Nanoparticulate double-heterojunction photocatalysts comprising TiO2(Anatase)/WO3/TiO2(Rutile) were produced by a sol-gel method. The resulting photocatalysts exhibit clear synergistic effects when tested toward the degradation of methyl orange under both UV and visible light. Kinetic studies indicate that the degradation rate on the best double-heterojunction photocatalyst (10 wt % WO3-TiO2) depends mainly on the amount of dye concentration, contrary to pure oxides in which the degradation rate is limited by diffusion-controlled processes. The synergistic effects were confirmed through systematic and careful studies including holes and OH radical formation, X-ray diffraction, electron microscopy, elemental analysis, UV-vis diffuse reflectance spectroscopy, and surface area analysis. Our results indicate that the successful formation of a double heterojunction in the TiO2(Anatase)/WO3/TiO2(Rutile) system leads to enhanced photoactivity when compared to individual oxides and commercial TiO2 P25.
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Affiliation(s)
- José Alfonso Pinedo-Escobar
- Unidad
Académica de Ciencias Químicas, Universidad Autónoma de Zacatecas, Campus Universitario Siglo XXI, km. 6 Carr. Zacatecas-Guadalajara
s/n Ejido La Escondida, Zacatecas 98160 Zacatecas, México
| | - Junpeng Fan
- Department
of Physics, Umeå University, Umeå 90187, Sweden
| | - Edgar Moctezuma
- Facultad
de Ciencias Químicas, Universidad
Aut́noma de San Luis Potosí, Av. Manuel Nava #6, San
Luis Potosí 78290 San Luis Potosí, México
| | - Christian Gomez-Solís
- División
de Ciencias e Ingenieŕa, Universidad
de Guanajuato, León 37150, Guanajuato, México
| | - Cristina Jared Carrillo Martinez
- Unidad
Académica de Ciencias Químicas, Universidad Autónoma de Zacatecas, Campus Universitario Siglo XXI, km. 6 Carr. Zacatecas-Guadalajara
s/n Ejido La Escondida, Zacatecas 98160 Zacatecas, México
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9
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Feng R, Tian K, Zhang Y, Liu W, Fang J, Khan MS, Wei Q, Wu R. Recognition of M2 type tumor-associated macrophages with ultrasensitive and biocompatible photoelectrochemical cytosensor based on Ce doped SnO 2/SnS 2 nano heterostructure. Biosens Bioelectron 2020; 165:112367. [PMID: 32729499 DOI: 10.1016/j.bios.2020.112367] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 05/27/2020] [Accepted: 06/05/2020] [Indexed: 02/08/2023]
Abstract
Tumor-associated macrophages (TAMs) play central roles in the regulation of tumor growth. TAMs can be differentiated into M1 and M2 types, which are responsible for the inhibition and growth of tumor tissues, respectively. Recognition of M2-TAMs is significant for the diagnosis and therapy of cancer, which is however severely limited due to the deficiency of selective and sensitive photoelectrochemical sensors. In this work, using Ce doped SnO2/SnS2 nano heterostructure as the highly sensitive platform, a photoelectrochemical sensor enabling the recognition of M2-TAMs was fabricated for the first time. By the decoration of CD163 antibody on the platform, the ultrasensitive photoelectrochemical sensor can selectively detect the CD163 protein on the surface of M2-TAMs. To our best knowledge, this is the first demonstration for recognition of M2-TAMs using photoelectrochemical method. The fabricated cytosensor has ultra-sensitive photocurrent response, applicable biological compatibility, high selectivity and relatively wide linear sensing range (5 × 101 to 1 × 105 cells/ml) with a low detection limit (50 cells/ml) for the detection of M2-TAMS. This kind of PEC cytosensor would provide a novel analysis and detection strategy for M2-TAMs.
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Affiliation(s)
- Ruiqing Feng
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
| | - Kaixuan Tian
- Department of Pediatric Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, 250021, PR China.
| | - Yifeng Zhang
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
| | - Wei Liu
- Department of Pediatric Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, 250021, PR China.
| | - Jinglong Fang
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
| | - Malik Saddam Khan
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
| | - Qin Wei
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
| | - Rongde Wu
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China; Department of Pediatric Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, 250021, PR China.
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10
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Ren W, Mei Z, Zheng S, Li S, Zhu Y, Zheng J, Lin Y, Chen H, Gu M, Pan F. Wavelength-Dependent Solar N 2 Fixation into Ammonia and Nitrate in Pure Water. RESEARCH 2020; 2020:3750314. [PMID: 32550602 PMCID: PMC7275971 DOI: 10.34133/2020/3750314] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 04/30/2020] [Indexed: 11/25/2022]
Abstract
Solar-driven N2 fixation using a photocatalyst in water presents a promising alternative to the traditional Haber-Bosch process in terms of both energy efficiency and environmental concern. At present, the product of solar N2 fixation is either NH4+ or NO3−. Few reports described the simultaneous formation of ammonia (NH4+) and nitrate (NO3−) by a photocatalytic reaction and the related mechanism. In this work, we report a strategy to photocatalytically fix nitrogen through simultaneous reduction and oxidation to produce NH4+ and NO3− by W18O49 nanowires in pure water. The underlying mechanism of wavelength-dependent N2 fixation in the presence of surface defects is proposed, with an emphasis on oxygen vacancies that not only facilitate the activation and dissociation of N2 but also improve light absorption and the separation of the photoexcited carriers. Both NH4+ and NO3− can be produced in pure water under a simulated solar light and even till the wavelength reaching 730 nm. The maximum quantum efficiency reaches 9% at 365 nm. Theoretical calculation reveals that disproportionation reaction of the N2 molecule is more energetically favorable than either reduction or oxidation alone. It is worth noting that the molar fraction of NH4+ in the total product (NH4+ plus NO3−) shows an inverted volcano shape from 365 nm to 730 nm. The increased fraction of NO3− from 365 nm to around 427 nm results from the competition between the oxygen evolution reaction (OER) at W sites without oxygen vacancies and the N2 oxidation reaction (NOR) at oxygen vacancy sites, which is driven by the intrinsically delocalized photoexcited holes. From 427 nm to 730 nm, NOR is energetically restricted due to its higher equilibrium potential than that of OER, accompanied by the localized photoexcited holes on oxygen vacancies. Full disproportionation of N2 is achieved within a range of wavelength from ~427 nm to ~515 nm. This work presents a rational strategy to efficiently utilize the photoexcited carriers and optimize the photocatalyst for practical nitrogen fixation.
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Affiliation(s)
- Wenju Ren
- School of Advanced Materials, Peking University, Shenzhen Graduate School, China.,School of Advance Manufacturing Engineering, Chongqing University of Posts and Telecommunications, Chongqing, China
| | - Zongwei Mei
- School of Advanced Materials, Peking University, Shenzhen Graduate School, China
| | - Shisheng Zheng
- School of Advanced Materials, Peking University, Shenzhen Graduate School, China
| | - Shunning Li
- School of Advanced Materials, Peking University, Shenzhen Graduate School, China
| | - Yuanmin Zhu
- Department of Materials Science and Engineering, Southern University of Science and Technology, China.,SUSTech Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, China
| | - Jiaxin Zheng
- School of Advanced Materials, Peking University, Shenzhen Graduate School, China
| | - Yuan Lin
- Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
| | - Haibiao Chen
- School of Advanced Materials, Peking University, Shenzhen Graduate School, China
| | - Meng Gu
- Department of Materials Science and Engineering, Southern University of Science and Technology, China
| | - Feng Pan
- School of Advanced Materials, Peking University, Shenzhen Graduate School, China
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11
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Yun J, Song Y, Cho I, Ko Y, Kwon CH, Cho J. High-performance electrochromic films with fast switching times using transparent/conductive nanoparticle-modulated charge transfer. NANOSCALE 2019; 11:17815-17830. [PMID: 31552994 DOI: 10.1039/c9nr06259a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
One of the most critical issues in electrochromic (EC) films based on transition metal oxides such as tungsten oxides (WOx) is their poor charge transfer property, which is closely related to EC performance. Herein, high-performance EC films with enhanced charge transport are prepared using small-molecule linkers and transparent/conductive nanoparticles (NPs). In this work, oleylamine (OAm)-stabilized WO2.72 nanorods (NRs) and OAm-stabilized indium tin oxide (ITO) NPs are layer-by-layer (LbL)-assembled with small-molecule linkers (tris(2-aminoethyl)amine, TREN) using a ligand-exchange reaction between bulky/insulating OAm ligands and TREN molecules. In this case, there is only one TREN layer between neighboring inorganic components (WO2.72 NRs and/or ITO NPs), resulting in a dramatic decrease in the separation distance. This minimized separation distance as well as the periodic insertion of transparent/conductive ITO NPs can significantly reduce the charge transfer resistance within WO2.72 NR-based EC films, which remarkably improves their EC performance. Compared to EC films without ITO NPs, the formed EC films with ITO NPs exhibit faster switching responses (4.1 times in coloration time and 3.5 times in bleaching time) and a maximum optical modulation of approximately 55.8%. These results suggest that electrochemical performance, including EC performance, can be significantly improved through structural/interfacial designing of nanocomposites.
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Affiliation(s)
- Junsang Yun
- Department of Chemical & Biological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea.
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12
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Bon-Ryul K, Kim KH, Ahn HJ. Novel tunneled phosphorus-doped WO 3 films achieved using ignited red phosphorus for stable and fast switching electrochromic performances. NANOSCALE 2019; 11:3318-3325. [PMID: 30720820 DOI: 10.1039/c8nr08793h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Simultaneous improvement of both the performance and stability of electrochromic devices (ECDs) to encourage their practical use in various applications, such as commercialized smart windows, electronic displays, and adjustable mirrors, by tuning the film structure and the electronic structure of transition metal oxides remains a challenging issue. In the present study, we developed novel tunneled phosphorus (P)-doped WO3 films via the ignition reaction of red P. The ignited red P, which can generate exothermic energy, was used as an attractive factor to create a tunneled structure and P-doping on the WO3 films. Therefore, by optimizing the effect of ignited red P on the WO3 films, tunneled P-doped WO3 films fabricated by using 1 wt% red P demonstrated a striking improvement of the EC performances, including both a fast switching speed (6.1 s for the colouration speed and 2.5 s for the bleaching speed) caused by the improvement of Li ion diffusion by the tunneled structure and electrical conductivity by P-doping WO3 and a superb colouration efficiency (CE, 55.9 cm2 C-1) as a result of increased electrochemical activity by the elaborate formation of the tunneled structure. Simultaneously, this film displayed a noticeable long-cycling stability due to a higher retention (91.5%) of transmittance modulation after 1000 electrochromic (EC) cycles as compared to bare WO3 films, which can mainly be attributed to the optimizing effect of the tunneled structure to generate an efficient charge transfer and an alleviated structural variation during the insertion-extraction of Li ions. Therefore, our results suggest a valuable and well-designed strategy to manufacture stable fast-switching EC materials that are fit for various practical applications of the ECDs.
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Affiliation(s)
- Koo Bon-Ryul
- Program of Materials Science & Engineering, Convergence Institute of Biomedical Engineering and Biomaterials, Seoul National University of Science and Technology, Seoul 01811, Korea
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Huang HM, Yang R, Tan ZH, He HK, Zhou W, Xiong J, Guo X. Quasi-Hodgkin-Huxley Neurons with Leaky Integrate-and-Fire Functions Physically Realized with Memristive Devices. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1803849. [PMID: 30461092 DOI: 10.1002/adma.201803849] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 10/25/2018] [Indexed: 06/09/2023]
Abstract
Artificial neurons with functions such as leaky integrate-and-fire (LIF) and spike output are essential for brain-inspired computation with high efficiency. However, previously implemented artificial neurons, e.g., Hodgkin-Huxley (HH) neurons, integrate-and-fire (IF) neurons, and LIF neurons, only achieve partial functionality of a biological neuron. In this work, quasi-HH neurons with leaky integrate-and-fire functions are physically demonstrated with a volatile memristive device, W/WO3 /poly(3,4-ethylenedioxythiophene): polystyrene sulfonate/Pt. The resistive switching behavior of the device can be attributed to the migration of protons, unlike the migration of oxygen ions normally involved in oxide-based memristors. With multifunctions similar to their biological counterparts, quasi-HH neurons are advantageous over the reported HH and LIF neurons, demonstrating their potential for neuromorphic computing applications.
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Affiliation(s)
- He-Ming Huang
- Laboratory of Solid State Ionics, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Rui Yang
- Laboratory of Solid State Ionics, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Zheng-Hua Tan
- Laboratory of Solid State Ionics, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Hui-Kai He
- Laboratory of Solid State Ionics, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Wen Zhou
- Laboratory of Solid State Ionics, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Jue Xiong
- Laboratory of Solid State Ionics, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Xin Guo
- Laboratory of Solid State Ionics, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
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Ranjith R, Krishnakumar V, Boobas S, Venkatesan J, Jayaprakash J. An Efficient Photocatalytic and Antibacterial Performance of Ni/Ce-Codoped CdS Nanostructure under Visible Light Irradiation. ChemistrySelect 2018. [DOI: 10.1002/slct.201801485] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Rajendran Ranjith
- Advanced Materials Laboratory; Department of Physics; Periyar University; Salem-636 011, Tamilnadu India
| | - Varadharajan Krishnakumar
- Advanced Materials Laboratory; Department of Physics; Periyar University; Salem-636 011, Tamilnadu India
| | - Singaram Boobas
- Advanced Materials Laboratory; Department of Physics; Periyar University; Salem-636 011, Tamilnadu India
| | - Jayaraman Venkatesan
- Advanced Materials Laboratory; Department of Physics; Periyar University; Salem-636 011, Tamilnadu India
| | - Jeyaram Jayaprakash
- Advanced Materials Laboratory; Department of Physics; Periyar University; Salem-636 011, Tamilnadu India
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