Piezo-photocatalysts in the field of energy and environment: Designs, applications, and prospects

Photocatalysis as an advanced oxidation process has been widely used in the fields of energy and environmental restoration. However, the reaction efficiency of photocatalysis is confined through the rapid recombination of photogenerated electron-hole pairs. Recently, emerging piezocatalysis can achieve high-efficiency conversion of mechanical energy, which has wonderful capability in relieving the energy crisis and the environment problem. Piezo-photocatalysis can perfectly combine the advantages of the two to improve the catalytic efficiency, because the piezoelectric effect can form an internal electric field inside a photocatalyst to improve the separation efficiency of photogenerated carriers, thereby obtaining more excellent photocatalysis performance; nevertheless, there is still a vast knowledge gap for the design, applications, and prospects of piezo-photocatalysts. Therefore, we organized a comprehensive review to better understand the research progress and research status of piezo-photocatalytic materials. We also supply a comprehensive overview of the research status of DFT for piezo-photocatalyst prediction and reaction mechanism analysis and elucidate the construction strategies (doping, crystal facet control, phase structure, surface modification, morphology, co-catalyst modification, composite hybridization, etc.) of the piezo-photocatalytic system and the underlying mechanisms for enhancing the catalytic performance. Aiming at the current challenges and prospects of piezo-photocatalysis, this review will clarify the development direction of piezo-photocatalysis, so as to achieve a deeper exploration and broaden the application of piezo-photocatalysis.