Halogen-Modulated 2D Coordination Polymers for Efficient Hydrogen Peroxide Photosynthesis under Air and Pure Water Conditions.

H O is a widely used eco-friendly oxidant and a potential energy carrier. Photocatalytic H O production from water and O is an ideal approach with the potential to address the current energy crisis and environmental issues. Three zig-zag two-dimensional coordination polymers (2D CPs), named CuX-dptz, were synthesized by a rapid and facile method at room temperature, showing preeminent H O photoproduction performance under pure water and open air without any additives. CuBr-dptz exhibits a H O production rate high up to 1874 μmol g  h , exceeding most reported photocatalysts under this condition, even comparable to those supported by sacrificial agents and O . The coordination environment of Cu can be modulated by halogen atoms (X=Cl, Br, I), which in turn affects the electron transfer process and finally determines the reaction activity. This is the first time that 2D CPs have been used for photocatalytic H O production in such challenging conditions, which provides a new pathway for the development of portable in situ H O photosynthesis devices.