Highly Efficient Photocatalytic H2O2 Production under Ambient Conditions via Defective In2S3 Nanosheets

Oxygen and water generating hydrogen peroxide (H 2 O 2 ) by optical drive is an extremely promising pathway, and the large amount of oxygen in air and natural sunlight illumination are excellent catalytic conditions. However, the separation efficiency of photogenerated electron–hole pairs greatly limits the photocatalytic efficiency, especially in the absence of sacrificial agents. Here, we report an In 2 S 3 nanosheet with an S vacancy (S v -In 2 S 3 ). The highest H 2 O 2 yield of S v -In 2 S 3 is 2.585 mmol g –1 h –1 under pure water, air, and sunlight ( P = 920 W/m 2 ), largely outperforming other reported photocatalysts for H 2 O 2 production. The experimental results show that the introduction of S v accelerates the separation of photogenerated electron–hole pairs and achieves efficient H 2 O 2 production through an oxygen reduction reaction. This efficient photosynthesis under ambient conditions allows solar-chemical conversion to take place in a truly cost-effective and sustainable way, opening up possibilities for practical production.