2D photocatalysts for hydrogen peroxide synthesis

Photocatalytic hydrogen peroxide (H2O2) synthesis, driven by solar energy, offers a sustainable and cleaner alternative for producing green H2O2 from water and oxygen. 2D photocatalysts have emerged as powerful materials for this purpose due to their unique physiochemical properties such as a flexible planar structure and large surface area. This review provides a comprehensive overview of the latest advances in 2D photocatalytic materials employed in H2O2 synthesis, including metal oxides, metal chalcogenides, bismuth-based materials, graphitic carbon nitrides (g-C3N4), metal-organic frameworks (MOFs), and covalent organic frameworks (COFs). Beginning with an extensive introduction to possible reaction routes for photocatalytic H2O2 synthesis, we summarize the common methods for H2O2 detection, crucial for obtaining reliable results in H2O2 studies. Additionally, we highlight molecular-level modification strategies for 2D photocatalysts, such as surface modification, ion doping, defect engineering, and heterojunction construction, which promote high-efficiency solar-to-chemical conversion for sustainable H2O2 photosynthesis. Furthermore, we discuss key issues and provide perspective outlooks for the efficient and sustainable generation of H2O2 in scale-up industrial production. This review offers in-depth insights into different reaction pathways of H2O2 synthesis and provides design principles for 2D photocatalysts to enhance H2O2 production, guiding the development of efficient photocatalysts for H2O2 synthesis.