With a proper band gap of ∼2.4 eV for solar light absorption and suitable valence band edge position for oxygen evolution, scheelite-monoclinic bismuth vanadate (BiVO) has become one of the most attractive photocatalysts for efficient visible-light-driven photoelectrochemical (PEC) water splitting. Several studies have indicated that surface modification of BiVO with a cocatalyst such as NiFe layered double hydroxide (LDH) can significantly increase the PEC water splitting performance of the catalyst. Herein, we experimentally investigated the charge transfer dynamics and charge carrier recombination processes by scanning electrochemical microscopy (SECM) with the feedback mode on the surface of BiVO and BiVO/NiFe-LDH as model samples. The ratio of rate constants for photogenerated hole () to electron () via the photocatalyst of BiVO/NiFe-LDH reacting with the redox couple is found to be five times larger than that of BiVO under illumination. In this case, the ratio of the rate constants / stands for the interfacial charge recombination process. This implies the cocatalyst NiFe-LDH suppresses the electron back transfer greatly and finally reduces the surface recombination. Control experiments with cocatalysts CoPi and RuO onto BiVO further verify this conclusion. Therefore, the SECM characterization allows us to make an overall analysis on the function of cocatalysts in the PEC water splitting system.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.analchem.1c01235 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Unlocking the Key to Photocatalytic Hydrogen Production Using Electronic Mediators for Z-Scheme Water Splitting.
J Am Chem Soc
January 2025
State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China.
A prevalent challenge in particulate photocatalytic water splitting lies in the fact that while numerous photocatalysts exhibit outstanding hydrogen evolution reaction (HER) activity in organic sacrificial reagents, their performance diminishes markedly in a Z-scheme water splitting system using electronic mediators. This underlying reason remains undefined, posing a long-standing issue in photocatalytic water splitting. Herein, we unveiled that the primary reason for the decreased HER activity in electronic mediators is due to the strong adsorption of shuttle ions on cocatalyst surfaces, which inhibits the initial proton reduction and results in a severe backward reaction of the oxidized shuttle ions.
View Article and Find Full Text PDFSynergistic high-entropy phosphides with phosphorus vacancies as robust bifunctional catalysts for efficient water splitting.
J Colloid Interface Sci
January 2025
State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 PR China. Electronic address:
High-entropy phosphides (HEPs) have garnered increasing interest as innovative electrocatalysts for water splitting, highlighted by their distinctive catalytic activity, elemental synergy, and tunable electronic configuration. Herein, a novel electrode comprising CoNiCuZnFeP nanocubes with rich phosphorus vacancies was fabricated through coprecipitation and phosphorization two-step method. The synergistic interaction among metal elements and the modulation of the electronic configuration by phosphorus vacancies augmentation enhance the catalytic performance for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).
View Article and Find Full Text PDFInserted-B atoms modulating electronic structure of Pt enhancing hydrogen evolution under Universal-pH.
J Colloid Interface Sci
January 2025
College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108 China. Electronic address:
The development of high-performance electrocatalysts for hydrogen evolution reaction (HER) in different pH conditionsis pivotal in producing green hydrogen, but remains challenging. Herein, we regulate the p-d orbitals hybridization between B and Pt for effective and durable HER at all pH ranges by controlling the inserted B atom. Consequently, the optimized B-doped Pt catalysts with 20 at.
View Article and Find Full Text PDFSynergistic spatial separation effect of internal electric field in ALD-generated BiFeO/CuO@Co Z-type heterojunction for enhanced photocatalytic water oxidation.
J Colloid Interface Sci
January 2025
College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong 518060, PR China; Guangdong Flexible Wearable Energy and Tools Engineering Technology Research Centre, Shenzhen University, Shenzhen 518060, PR China. Electronic address:
Altering the electron distribution within a catalyst to manipulate internal charge migration pathways is an effective strategy for achieving high efficiency in carrier separation and migration, which is essential for the advancement of photocatalytic water oxidation technologies. We have employed atomic layer deposition (ALD) to construct a BiFeO/CuO (BFO/CuO) heterojunction with a specific CuO thickness, resulting in a Z-type junction (BFO/CuO50) characterized by a robust internal electric field. This junction facilitates the spatial separation of charge carriers, thereby enhancing their migration efficiency.
View Article and Find Full Text PDFNanofibrous Ru/SnO heterostructure as robust bifunctional electrocatalyst for high-performance overall hydrazine splitting and Zn-hydrazine battery.
J Colloid Interface Sci
January 2025
Alan G. MacDiarmid Institute, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, PR China. Electronic address:
Water electrolysis represents a green and efficient strategy for hydrogen (H) production. However, the four-electron transfer process involved in its anodic oxygen evolution reaction (OER) half-reaction restricts the H generation rate. Employing hydrazine oxidation reaction (HzOR) as a substitute for OER in H generation can dramatically reduce energy consumption.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!