Potential of Bi2WO6-based heterojunction photocatalysts for environmental remediation

Bismuth tungstate (Bi2WO6)-based photocatalytic materials have become a research hotspot in photocatalytic energy conversion and environmental remediation due to their low-toxicity, abundant, ease of preparation, chemical stability as well as excellent structural, electrical and optical properties. However, the main disadvantage of pure semiconductors, including Bi2WO6, is associated with the rapid recombination of photogenerated charge carriers, which leads to low activity. As one of the approaches to solve this challenge, the preparation of heterojunctions based on Bi2WO6 has been proven as the most efficient, reliable and promising strategy. This critical review explores the use of Bi2WO6-based heterojunction photocatalysts with a focus on Z-scheme and S-scheme composites for environmental remediation, including air purification and wastewater treatment. Moreover, the challenges and opportunities are considered to further insight into developing new photocatalytic materials with their future commercialization on an industrial scale. Some new approaches for further improving Bi2WO6-based photocatalysts, such as optimization of preparation method, hetero- and homo-substitution of A-site or B-site (atomic regulation) and the use of support matrix, are highlighted.