Layered bismuth-based photocatalysts

Semiconductor photocatalysis has received considerable interdisciplinary attentions and research interests owing to its versatile applications. Layered bismuth-based (LBB) materials, featured by layered structure built by [Bi2O2]2+ slices and interleaved anions or/and anionic groups, show huge potentials in solar energy catalytic conversion due to their unique crystal structure, diverse composition, rich atomic coordination and favorable hybrid electronic band structure. In this review, we provide a comprehensive, systematic and timely summary on the LBB-based materials applied in photocatalysis, which start with the classification, characteristics, and synthesis. Subsequently, LBB photocatalysts are classified into Sillén-structured, Aurivillius-structured, Sillén-Aurivillius-structured and Sillén/Aurivillius-related structured photocatalysts based on the interleaved unit types, and all kinds of strategies for improving their photocatalytic performance are presented in details, including microstructure regulation (morphology control and facet engineering), crystal structure regulation (elements doping, crystal vacancy creation, layered structure regulation and polar enhancement) and heterojunction construction (semiconductor/LBB heterojunctions, carbon/LBB composites, polymer/LBB composites and multicomponent heterojunctions). Comprehensive photocatalytic applications of LBB materials, including pollutants purification, bacterial disinfection, water splitting, CO2 reduction, N2 reduction, H2O2 production/decomposition, selective organic synthesis, photoelectrocatalysis, as well as photocatalysis-assisted piezocatalysis and electrochemical energy storage are introduced in the respective type. Finally, concluding perspectives and outlook towards the future development of LBB photocatalysts are provided. This review is expected to furnish a sweeping guideline for the in-depth understanding and rational design of LBB photocatalysts, and inspire new concepts and advancements in other booming fields for energy and environmental applications.