Nanostructured photocatalysts: Introduction to photocatalytic mechanism and nanomaterials for energy and environmental applications

Abstract Nanomaterials play a key role in modern photocatalytic applications, including hydrogen evolution reaction, oxygen evolution reaction, CO2 reduction reaction, organic synthesis, organic decomposition, and toxic gas removal. In this chapter, the mechanism for each reaction listed above is summarized and discussed. Furthermore, the emerging nanomaterials that have been effectively used in photocatalytic applications such as carbon-based materials, transition metal oxides, transition metal chalcogenides, transition metal carbides, metal-organic frameworks, and covalent organic frameworks are introduced. The optical and physical properties of materials that enable their catalytic activity under ultraviolet-visible light irradiation are highlighted. Although photocatalysis is promising with many advantages, the performance outcomes are still not as efficient as catalysis. Hence, more theoretical and practical studies are suggested to further promote photocatalytic efficiency.