WO ₃ nanoflake photoanodes with suitable bulk oxygen vacancies and reduced surface oxygen vacancies are synthesized by hydrogen annealing and ozone treatment, which exhibit excellent photoelectrochemical performance.

Most Bi-based photoelectrodes have suitable band gaps and can effectively promote the water oxidation reaction. However, simple preparation methods for Bi-based binary metal oxides as photoanodes are scarce. This paper describes a simple hydrothermal anion exchange method to synthesize Bi-based binary metal oxides with controlled morphologies. This synthesis process uses BiOI as the template and Bi source, which is eventually converted to Bi-based porous nanoflake photoanodes upon reaction with MO_x (M = W, V, and Mo)-containing precursors. The photoanodes show well-shaped porous nanoflake morphologies and exhibit impressive photoelectrochemical properties compared to Bi-based photoanodes synthesized by conventional methods. These three samples possess long-term stability under solar irradiation and show considerable photocurrent for sulfite oxidation.

This communication describes an efficient co-catalyst Co₃O₄ nanoparticle with a tunable two-electron water oxidation reaction pathway in photoelectrochemical H₂O₂ production.

ZnCdS quantum dots (QDs) are highly coveted in photocatalysis research for their exceptional visible-light responses and high light-absorption coefficients. However, their practical application is hindered by their tendency to aggregate, due to having high surface energies. To address this issue, herein, a heterostructure is synthesized by growing ZnCdS QDs with a size of approximately 5 nm onto the surface of a two-dimensional (2D) covalent organic framework (COF), TpPa-1-COF. This approach suppresses the aggregation of the QDs and improves their stability. The ZnCdS/TpPa-1-COF composite exhibited a peak hydrogen evolution rate of 6244.16 µmol·g⁻¹·h⁻¹, which was 2.89 and 4.18 times greater than that of ZnCdS and TpPa-1-COF, respectively. The zero-dimensional/two-dimensional (0D/2D) heterojunction formed by ZnCdS and TpPa-1-COF generates a strong interfacial force, which is attributed to the intimate contact between the interfaces. Tight connections accelerate charge separation, improve the utilisation of reduced electrons, and reduce the extent of agglomeration of the ZnCdS QDs, thereby resulting in high hydrogen production activity of the composites. Meanwhile, the photocatalytic mechanism is studied using Kelvin probe force microscopy and theoretical calculations. This study offers a novel approach for creating sulfide photocatalysts and is crucial for investigating the potential practical applications of the related photocatalysts.