Constructing an all zero-dimensional CsPbBr3/CdSe heterojunction for highly efficient photocatalytic CO2 reduction

Metal halide perovskite quantum dots (QDs) are regarded as one of the promising photocatalysts for CO2 reduction because of their unique optoelectronic properties. However, severe charge recombination and insufficient CO2 absorption/activation have limited photocatalytic CO2 reduction. Herein, we report an efficient 0D/0D CsPbBr3/CdSe heterojunction consisting of CdSe QDs in situ grown on CsPbBr3 QDs for high-performance photocatalytic CO2 reduction using water as the electron donor in organic solution. The type-II 0D/0D heterojunction with the strong electronic coupling of Pb–Se and Br–Cd bonds between CdSe and CsPbBr3 facilitates fast electron transfer. Moreover, the specific abundant edge- and corner-sites of CdSe accelerate the CO generation by forming a Cd–C2O4− adduct, enabling superior CO2 activation capacity and efficient CO2 conversion into CO. Consequently, assisted by water to provide electrons and protons, the yield of main product CO reaches 115.26 μmol g−1, which is 4.6-fold higher than that of pristine CsPbBr3. This study is expected to provide a new way to fabricate high-performance perovskite-based catalysts in the field of photocatalysis.