- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Peanut-type fiber based hydrogen sensor coated by PDMS covered with WO <sub/>3</sub> /SiO <sub/>2</sub>
摘要： A hydrogen sensor based on a peanut-type fiber coated with a film of PDMS covered with WO3/SiO2 hybird powder was proposed. Mach-Zehnder interferometer is composed of two peanut-type structures and a single-mode optical fiber. Two peanut-type surfaces were coated with PDMS films coated with WO3/SIO2 powder. The proposed sensor has the sensitivity of 0.47db/% with a linear correlation of 98.3% in the concentration range of 0% - 0.901%.
关键词： Peanut-type fiber,PDMS,WO3,Hydrogen sensor
更新于2025-09-16 10:30:52
-
Controlled joule-heating of suspended glassy carbon wires for localized chemical vapor deposition
摘要： This paper demonstrates for the first time localized chemical vapor deposition of WO3-x on a suspended glassy carbon wire. A process based on the photopatterning of an SU-8 scaffold, the near-field electrospinning of an SU-8 fiber, and their pyrolysis yields a monolithic carbon structure featuring a glassy carbon wire of known diameter and length, suspended on a glassy carbon scaffold. The temperature required for the deposition of WO3-x is generated by passing current through the wire, which causes Joule heating. The deposition starts in the midpoint of the wire, and extends to its ends as the current is increased. The thickness and length of the coating are functions of the imposed current. The evolution of the coating can be monitored in real time by measuring the voltage vs current characteristic of the wire. We have deposited WO3-x coatings with thickness from 71 nm to 1.4 μm, in glassy carbon wires with diameters between 780 nm and 2.95 μm. The coatings are uniform and polycrystalline. The suspended glassy carbon wire is a generic platform for the deposition of many transition metal oxide (TMO) coatings, and opens the door to carbon-TMO structures for applications including catalysis and gas sensing.
关键词： glassy carbon wire,gas sensing,localized chemical vapor deposition,WO3-x,catalysis,Joule heating,transition metal oxide
更新于2025-09-12 10:27:22
-
Performance of WO <sub/>3</sub> -Incorporated Carbon Electrodes for Ambient Mesoscopic Perovskite Solar Cells
摘要： The stability of perovskite solar cells (PSC) is often compromised by the organic hole transport materials (HTMs). We report here the effect of WO3 as an inorganic HTM for carbon electrodes for improved stability in PSCs, which are made under ambient conditions. Sequential fabrication of the PSC was performed under ambient conditions with mesoporous TiO2/Al2O3/CH3NH3PbI3 layers, and, on the top of these layers, the WO3 nanoparticle-embedded carbon electrode was used. Different concentrations of WO3 nanoparticles as HTM incorporated in carbon counter electrodes were tested, which varied the stability of the cell under ambient conditions. The addition of 7.5% WO3 (by volume) led to a maximum power conversion efficiency of 10.5%, whereas the stability of the cells under ambient condition was ～350 h, maintaining ～80% of the initial efficiency under light illumination. At the same time, the higher WO3 concentration exhibited an efficiency of 9.5%, which was stable up to ～500 h with a loss of only ～15% of the initial efficiency under normal atmospheric conditions and light illumination. This work demonstrates an effective way to improve the stability of carbon-based perovskite solar cells without affecting the efficiency for future applications.
关键词： inorganic hole transport materials,stability,perovskite solar cells,carbon electrodes,WO3,ambient conditions
更新于2025-09-12 10:27:22
-
Interfacial growth of the optimal BiVO4 nanoparticles onto self-assembled WO3 nanoplates for efficient photoelectrochemical water splitting
摘要： Photoelectrochemical water splitting is the most efficient green engineering approach to convert the sun light into hydrogen energy. The formation of high surface area core-shell heterojunction with enhanced light-harvesting efficiency, elevated charge separation, and transport are key parameters in achieving the ideal water splitting performance of the photoanode. Herein, we demonstrate a first green engineering interfacial growth of the BiVO4 nanoparticles onto self-assembled WO3 nanoplates forming WO3/BiVO4 core-shell heterojunction for efficient PEC water splitting performance. The three different WO3 nanostructures (nanoplates, nanobricks, and stacked nanosheets) were self-assembled on fluorine doped tin oxide glass substrates via hydrothermal route at various pH (0.8–1.2) of the solutions. In comparison to nanobricks and stacked nanosheets, WO3 nanoplates displayed considerably elevated photocurrent density. Moreover, a simple and low cost green approach of modified chemical bath deposition technique was established for the optimal decoration of a BiVO4 nanoparticles on vertically aligned WO3 nanoplates. The boosted photoelectrochemical current density of 1.7 mA cm?2 at 1.23 V vs. reversible hydrogen electrode (RHE) under AM 1.5 G illumination was achieved for the WO3/BiVO4 heterojunction which can be attributed to a suitable band alignment for the efficient charge transfer from BiVO4 to WO3, increased light harvesting capability of outer BiVO4 layer, and high charge transfer efficiency of WO3 nanoplates.
关键词： Green hydrogen,Photoelectrochemical water oxidation,WO3/BiVO4 heterojunction,Low cost,Core-shell
更新于2025-09-12 10:27:22
-
Surface modification of sputter deposited γ-WO3 thin film for scaled electrochromic behaviour
摘要： In this research work, the synthesis and the electrochromic (EC) performance of the active material (γ-WO3) is reported. Nanoporous γ-WO3 thin ?lm was grown directly on the indium tin oxide (ITO) coated glass substrate using DC magnetron sputtering in a reactive environment (Ar:O2 = 2:1) at room temperature (RT). To achieve the nanoporous-nanocrystalline behaviour of the active material, a thermal treatment (250 °C) was given, which modi?ed the compact ?lm surface into nanospheres. This surface modi?cation is responsible to alter the physical, optical and electrochromic properties of the active material. The physical properties of the active material were probed in detail using X-ray di?raction (XRD), Field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and energy-dispersive X-ray analysis (EDX). The optical and electrochromic behaviour of the active electrode material was analyzed using UV–Vis spectroscopy and cyclic voltammetry (CV). It has been found that the modi?ed electrode exhibited large optical modulation (46%), high reversible redox behaviour (higher current density) and good cyclic stability at least upto 500 cycles, causes scaled EC behaviour. This electrochemically active architecture allow one to fabricate the device for energy harvesting applications. Our work indorse human comfort with ?nancial bene?ts and may play a crucial role in “green nanotechnology”.
关键词： Transmittance,WO3 thin ?lms,Sputtering,Nanoporous,Electrochromism
更新于2025-09-11 14:15:04
-
Designing WO <sub/>3</sub> /CdIn <sub/>2</sub> S <sub/>4</sub> type-II heterojunction with both efficient light absorption and charge separation for enhanced photoelectrochemical water splitting
摘要： WO3 is a typical photoanode material for photoelectrochemical (PEC) water splitting. However, the PEC activity of WO3 photoanode is limited by its poor visible light absorption as well as severe carrier recombination at the electrode/electrolyte interface. Herein, we integrate small-band-gap CdIn2S4 nanoplates with hydrothermally grown WO3 nanowall arrays to form into a three-dimensional (3D) WO3/CdIn2S4 heterojunction through a chemical bath deposition process. The synthesis parameters of CdIn2S4, including reaction time and temperature, have been tuned to optimize the PEC performance. The WO3/CdIn2S4 composite photoanode prepared at 50 °C for 5 h exhibits the highest photocurrent of 1.06 mA cm?2 at 1.23 V versus reversible hydrogen electrode without the presence of holes scavenger, which is about 5.9 times higher than that of bare WO3 photoanode. The band alignment between WO3 and CdIn2S4 is confirmed by the ultraviolet–visible light absorption spectra and ultraviolet photoelectron spectra. The PEC performance enhancement is attributed to the enhanced light absorption benefiting from the small band gap of CdIn2S4 and efficient charge separation originating from the type-II alignment between WO3 and CdIn2S4.
关键词： photoanode,WO3,CdIn2S4,photoelectrochemical water splitting,heterojunction
更新于2025-09-11 14:15:04
-
TiO <sub/>2</sub> /WO <sub/>3</sub> Bilayer as Electron Transport Layer for Efficient Planar Perovskite Solar Cell with Efficiency Exceeding 20%
摘要： It is crucial to retard the carrier recombination and minimize the energy loss at the transparent electrode/electron transport layer (ETL)/perovskite absorber interfaces to improve the performance of the perovskite solar cells (PSCs). Here, a bilayered TiO2/WO3 film is designed as ETL by combining atomic layer deposition (ALD) technology and spin-coating process. The ALD-TiO2 underlayer fills the fluorine-doped tin oxide (FTO) valleys and makes the surface smoother, which effectively avoids the shunt pathways between perovskite layer and FTO substrate and thereby suppresses electron–hole recombination at the interface. Moreover, the presence of hydrophilic TiO2 underlayer is helpful in forming a uniform and compact WO3 layer which is beneficial for extracting electron from perovskite to ETL. Meanwhile, the lower valance band minimum level of TiO2 relative to WO3 can efficiently enhance the hole-blocking ability. By employing the optimized TiO2 (7 nm)/WO3 bilayer as ETL, the resulting cell exhibits an obviously enhanced power conversion efficiency of up to 20.14%, which is much better than the single WO3 or TiO2 ETL based device. This work is expected to provide a viable path to design ultrathin and compact ETL for efficient PSCs.
关键词： electron transport layer,perovskite solar cells,TiO2,WO3,ALD
更新于2025-09-11 14:15:04
-
Large tunability of strain in WO3 single-crystal microresonators controlled by exposure to H2 gas
摘要： Strain engineering is one of the most effective approaches to manipulate the physical state of materials, control their electronic properties, and enable crucial functionalities. Because of their rich phase diagrams arising from competing ground states, quantum materials are an ideal playground for on-demand material control, and can be used to develop emergent technologies, such as adaptive electronics or neuromorphic computing. It was recently suggested that complex oxides could bring unprecedented functionalities to the field of nanomechanics, but the possibility of precisely controlling the stress state of materials is so far lacking. Here we demonstrate the wide and reversible manipulation of the stress state of single-crystal WO3 by strain engineering controlled by catalytic hydrogenation. Progressive incorporation of hydrogen in freestanding ultra-thin structures determines large variations of their mechanical resonance frequencies and induces static deformation. Our results demonstrate hydrogen doping as a new paradigm to reversibly manipulate the mechanical properties of nanodevices based on materials control.
关键词： Tungsten Trioxide,Hydrogen Doping,MicroElectroMechanical Systems,WO3,Transition Metal Oxides,Oxide MEMS,Strain Engineering,Chemical Strain
更新于2025-09-11 14:15:04
-
Efficient Photocatalytic Hydrogen Production Achieved by WO3 Coupled with NiP2 Over ZIF-8
摘要： The photo-catalyst WO3/NiP2@ZIF-8 was synthesized by modifying the WO3 with NiP2@MOFs structure. High H2 production was achieved (341.2 μmol and 11.3 times than pure WO3 after 5 h) and the catalytic property of WO3 was improved. The XRD, FESEM and TEM were used to characterize and analyze the crystalline phase structure, namely, WO3 has nanowire structure and good crystalline phase, meanwhlie, ZIF-8 exhibits regular dodecahedron morphology. The catalysts were characterized and analyzed by electrochemical, steady-state and transient state, those results show that the composite has more efficient charge separation effect and better electrical performance than single catalyst, which provides a reliable basis for relative higher H2 production activity. The band gap structure and elemental valence of the composite catalysts were calculated and analyzed by UV–Vis DR and XPS, respectively. The possible reaction equation and H2 production mechanism of WO3/NiP2@ZIF-8 in HER were proposed.
关键词： NiP2@ZIF-8,Photocatalytic H2 production,WO3,Band gap structure
更新于2025-09-11 14:15:04
-
Facile preparation of nanoflower structured WO3 thin film on etched titanium substrate with high photoelectrochemical performance
摘要： In this study, a nanoflower structured WO3 thin film has been prepared on an etched titanium substrate using a WO3 seeds-assisted hydrothermal reaction method. The WO3 nanoflower-like structure appeared when the growth time arrived at 4.75 h. Subsequently, this film went into a rapid growth stage. The nanoflower (NF) structured WO3 thin film with 8 h of hydrothermal reaction possessed the best photoelectrochemical performance. The photoinduced current density was 2.0 mA·cm?2 at a bias potential of 1.23 V (vs. Ag/AgCl) under the illumination by a simulated sunlight (100 mW/cm2) with a filter air mass (AM) 1.5 G. The improvement of the photoelectrochemical performance of the nanoflower structured WO3 can be attributed to three aspects. Firstly, the light absorption capacity could be increased by the nanoflower structure. Secondly, the reactive sites could be enhanced due to the increased specific surface area of the nanoflower structured WO3. Finally, a direct transfer channel for the photogenerated electrons could be formed by the definite 2-dimentional WO3 nanoflakes linked with the Ti substrate.
关键词： Nanoflower,Etched titanium,WO3,Photoanode
更新于2025-09-11 14:15:04