- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Probing the Advantageous Photosensitization Effect of Metal Nanoclusters over Plasmonic Metal Nanocrystals in Photoelectrochemical Water Splitting
摘要： Atomically precise metal nanoclusters (NCs)-based photocatalytic systems have garnered enormous attention owing to the fascinating merits including unique physicochemical properties, quantum confinement effect and photosensitization effect, which are distinct from conventional metal nanocrystals (NYs). Nevertheless, systematic comparison between electrons photoexcited from metal NCs and hot electrons from surface plasmonic resonance (SPR) effect of metal NYs in boosting photoelectrochemical water splitting reaction remains blank. Here, we report the strict and comprehensive comparison on the capability of electrons photoexcited from glutathione-capped gold nanoclusters (Aux@GSH) and hot electrons from plasmonic excitation of gold nanoparticles (Au NYs) self-transformed from Aux@GSH to trigger the PEC water splitting reaction under visible light irradiation. The results indicate photoelectrons of Aux NCs trigger more efficient charge transport rate than hot electrons of plasmonic Au NYs in terms of light harvesting and conversion efficiency under the identical conditions. Moreover, charge transfer characteristics in Aux NCs and Au NYs-based PEC systems were established. This work would reinforce our deep understanding on these two pivotal sectors of metal nanomaterials for solar energy conversion.
关键词： photosensitization effect,plasmonic metal nanocrystals,charge transfer,photoelectrochemical water splitting,metal nanoclusters
更新于2025-09-23 15:19:57
-
Metal-Reduced WO3a??x Electrodes with Tunable Plasmonic Resonance for Enhanced Photoelectrochemical Water Splitting
摘要： Photoelectrochemical (PEC) water splitting is one of the most promising green technologies for producing renewable clean hydrogen energy. Developing plasmonic semiconductors with tunable plasmonic resonance to visible light has drawn increasing attention in view of utilizing abundant low-energy photons for solar-to-chemical conversion. Herein, we demonstrate for the first time that the WO3 electrode can be partly reduced by various metal foils in acid solution, showing strong localized surface plasmon resonance (LSPR) in the visible-to-near-infrared (Vis–NIR) region. The LSPR can be precisely tuned by using metal foils with different standard electrode potentials for different reaction times, and the LSPR peak position strongly depends on the concentration of W5+ in the WO3?x electrodes. A photocurrent density of 0.79 mA·cm?2 at 1.23 VRHE, which is twice that of pristine one, is obtained over an optimally reduced WO3?x electrode. The enhanced PEC water splitting performance is ascribed to the increased light absorption, conductivity and charge carrier concentration.
关键词： photoelectrochemical water splitting,semiconductor,plasmonic resonance,metal foil,tungsten oxide
更新于2025-09-23 15:19:57
-
High-Performance Silicon Photoanode Enabled by Oxygen Vacancy Modulation on NiOOH Electrocatalyst for Water Oxidation
摘要： Silicon (Si) is an attractive photoanode material for photoelectrochemical (PEC) water splitting. However, Si photoanode is highly challenging due to its poor stability and catalytic inactivity toward oxygen evolution reaction (OER). Integration of highly active electrocatalysts with Si photoanodes has been considered as an effective strategy to improve OER performance through accelerates reaction kinetics and inhibits Si photocorrosion. In this work, ultra-small NiFe nanoparticles are deposited onto n-Si/Ni/NiOOH surface to improve the activity and stability of Si photoanode by engineering the electrocatalyst and Si interface. Ultra-small NiFe can introduce oxygen vacancies via modulating the local electronic structure of Ni hosts in NiOOH electrocatalyst for fast charge separation and transfer. Besides, NiFe nanoparticles also can serve as co-catalyst exposure more active sites and as protection layer prevents Si photocorrosion. The as-prepared n-Si/Ni/NiOOH/NiFe photoanode exhibits excellent OER activity with an onset potential of 1.0 V versus reversible hydrogen electrode (RHE) and a photocurrent density of ～25.2 mA cm-2 at 1.23 V versus RHE. This work provides a promising approach to design high-performance Si photoanodes by surface electrocatalyst engineering.
关键词： photoelectrochemical water splitting,oxygen vacancies,OER activity,NiFe nanoparticles,Silicon photoanode
更新于2025-09-23 15:19:57
-
A novel electrochemical method for simultaneous measurement of real-time potentials and photocurrent of various photoelectrochemical systems
摘要： Two-electrode configuration is preferably used in practical application of various photoelectrochemical systems, such as green fuel production and cathodic protection. Photo electrodes are extendedly studied but the effects of the dark electrodes on overall performance of PEC systems are not experimentally figured out. To address this issue, herein, a novel electrochemical method achieving simultaneous measurement of photocurrent and real-time potential of the photo electrode and the dark electrode is proposed. With this method, the actual band positions and band bending of the photo electrode under photocurrent going through can be determined correctly. By investigating photoelectrochemical hydrogen production and cathodic protection with ZnO photo anodes, it is revealed that the amplitude of photocurrent is not solely determined by the number of light generated electrons on the photo electrode but also strongly affected by their consuming rate for electrochemical reactions on the dark electrode. These applications demonstrate the practicality, reliability and universality of the proposed method for comprehensive understanding the reactions of various photoelectrochemical systems and eventually for their better development.
关键词： Semiconducting materials,Artificial solar synthesis,Photoelectrochemical cathodic protection,Photocatalysis,Photoelectrochemical water splitting
更新于2025-09-19 17:15:36
-
Recent progresses in the design of BiVO4-based photocatalysts for efficient solar water splitting
摘要： Photocatalysis and photoelectrocatalysis are both considered as promising routes to solve energy and environmental crises. Particularly, photoelectrochemical (PEC) water splitting has been extensively studied in the search for sustainable ways of converting solar energy into chemical energy to produce energy-dense fuel with minimal carbon footprint. Bismuth vanadate (BiVO4) has attracted a lot attention in recent years due to its visible-light activity, favorable conduction and valence band edge positions, and low-cost facile synthesis route. However, BiVO4 still suffers from low carrier separation efficiency and slow oxygen evolution kinetics on its surface. To overcome these weaknesses, various modification strategies, including nanostructural morphology control, element doping, heterostructures (particularly Z-scheme), plasmonic enhancement and surface passivation, have been proposed and implemented to improve its PEC activity. This short review summarizes the most recent advances on the designs of BiVO4-based photocatalysts and photoanodes. Some of the best-performing BiVO4–based photo-electrode structures to date are demonstrated, and the critical parameters that contribute to these outstanding performances are discussed.
关键词： Solar energy harvesting,BiVO4,Photocatalyst,Photoelectrochemical water splitting
更新于2025-09-19 17:15:36
-
Synthesis of Cu2O/Carbon film/NiCoB-GO Heterostructure Photocathode for Efficient Photoelectrochemical Water Splitting
摘要： Photoelectrochemical (PEC) water splitting offers a promising way to convert solar energy to chemical energy. The electron transfer rate and surface-catalyzed ability toward hydrogen evolution reaction (HER) play the key roles in the efficiency of PEC water splitting. In this work, a Cu2O/Carbon film/NiCoB-GO heterostructure photocathode is fabricated. Among them, thickness-controllable carbon film served as the electron transport and protective layer with favourable optical property, NiCoB-GO amorphous catalyst displays the efficient performance towards HER in neutral condition. The optimized photocathode shows the PEC-HER performance with a photocurrent density of -2.9 mA/cm2 at 0 V vs. RHE, and it also presents better stability than bare Cu2O. This work provides a novel heterostructure photocathode for promoting solar-driven PEC water splitting efficiently.
关键词： Femtosecond transient absorption spectroscopy,Photoelectrochemical water splitting,Electron transport path,Carbon film,Amorphous catalyst
更新于2025-09-19 17:15:36
-
Niobium incorporated WO3 nanotriangles: Band edge insights and improved photoelectrochemical water splitting activity
摘要： In this work, a facile hydrothermal method is proposed to fabricate Nb-doped WO3 nanotriangle thin films, and their band edge properties and photoelectrochemical water splitting activity were explored. The process of doping and thin film formation was simultaneously achieved in a single step hydrothermal condensation of peroxopolytungstic acid solution containing Nb precursor. The crystallographic study reveals that doping of Nb into WO3 lattice obstructs the reconstructive transformation of orthorhombic WO3·0.33H2O during annealing consequently producing hexagonal phase instead of the monoclinic phase. The insertion of Nb causes the increase in band gap and induces oxygen vacancies in WO3. Uniform distribution of Nb in WO3 was observed containing majorly Nb5+ valence and a small amount of Nb4+ state. PEC characterization showed the increase in photocurrent, (at AM 1.5G illumination) incident photon to current and photoconversion efficiency values of WO3 upon Nb doping. Band edge analysis revealed that both conduction and valence band edge of WO3 show downward shift towards higher potential vs. RHE whereas the Fermi level show upward shift as a result of Nb doping.
关键词： Band edge,Niobium,Reconstructive transformation,Tungsten oxide,Photoelectrochemical water splitting
更新于2025-09-19 17:15:36
-
Tailored TiO <sub/>2</sub> Protection Layer Enabled Efficient and Stable Microdome Structured pa??GaAs Photoelectrochemical Cathodes
摘要： Group III–V compound semiconductors are a promising group of materials for photoelectrochemical (PEC) applications. In this work, a metal assisted wet etching approach is adapted to acquiring a large-area patterned microdome structure on p-GaAs surface. In addition, atomic layer deposition is used to deposit a TiO2 protection layer with controlled thickness and crystallinity. Based on a PEC photocathode design, the optimal configuration achieves a photocurrent of ?5 mA cm?2 under ?0.8 V versus Ag/AgCl in a neutral pH electrolyte. The TiO2 coating with a particular degree of crystallization deposited via controlled temperature demonstrates a superior stability over amorphous coating, enabling a remarkably stable operation, for as long as 60 h. The enhanced charge separation induced by favorable band alignment between GaAs and TiO2 contributes simultaneously to the elevated solar conversion efficiency. This approach provides a promising solution to further development of group III–V compounds and other photoelectrodes with high efficiency and excellent durability for solar fuel generation.
关键词： atomic layer deposition,GaAs,TiO2 coating,photocathode stability,photoelectrochemical water splitting
更新于2025-09-19 17:13:59
-
Plasmonic gold sensitization of ZnO nanowires for solar water splitting
摘要： This paper reports the synthesis of plasmonic gold sensitized ZnO nanowires by chemical vapor deposition and subsequent photoreduction method. The well sensitization of Au nanoparticles with mean diameter of 5.3 nm on ZnO nanowires yield a higher photocurrent density of 1.06 mAcm-2 under illumination. Accordingly, Au nanoparticles on ZnO nanowires reveals the maximum photoelectrochemical water splitting efficiency of 0.45% at + 0.8 VRHE, which is higher than the ZnO nanowires (0.22% at + 0.8 VRHE). The enhanced photocurrent density and efficiency is due to the effective charge separation and transportation originating from metal support interaction, 1D nanostructure as well as surface plasmon resonance effect of Au nanoparticles.
关键词： Interfaces,Photoelectrochemical water splitting,Chemical vapor deposition,ZnO nanowires,Au nanoparticles
更新于2025-09-19 17:13:59
-
Electronic doping-enabled transition from n- to p-type conductivity over Au@CdS core–shell nanocrystals toward unassisted photoelectrochemical water splitting
摘要： Here we show a novel strategy for tailoring the synergistic electrical properties of metal@semiconductor hybrid nanocrystals (HNCs) based on cation exchange-enabled electronic doping. As a demonstration, the conductive nature of Au@CdS core–shell HNCs was changed from n- to p-type by introducing Cu dopants into the CdS shell. The dependence of the conductivity type on the dopant concentration in the HNCs is disclosed by combined photoelectrochemical (PEC) studies. Moreover, a tandem PEC cell consisting of an undoped Au@CdS photoanode and a Cu-doped Au@CdS photocathode respectively modified with cocatalysts is fabricated, which displayed stable H2 and O2 evolution in unassisted PEC overall water splitting.
关键词： photoelectrochemical water splitting,electronic doping,cation exchange,metal@semiconductor hybrid nanocrystals
更新于2025-09-16 10:30:52