1 All-Inorganic CsPbBr3 Nanocrystals: Gram-Scale Mechanochemical Synthesis and Selective Photocatalytic CO2 Reduction to Methane

We reported a fast and convenient mechanochemical synthesis of CsPbBr3 perovskite nanocrystals with scale-up capability and control over crystal size and morphology. Furthermore, we explored their use for gas-phase photocatalytic CO2 reduction using water vapor under simulated sun light. More attractively, the mechanochemically prepared composite of CsPbBr3 nanosheets with Cu-loaded reduced graphene oxide (Cu-RGO) showed significantly improved activity for CO2 photoreduction to CH4 with a selectivity of 98.5% on an electron basis and a remarkable apparent quantum efficiency of 1.26% at 523 nm. These results will contribute to the rational design and application of halide perovskites for CO2 photocatalytic reduction. This work has been accepted for publication in ACS Applied Energy Materials (DOI:10.1021/acsaem.0c00195). This dataset includes XRD, UV-vis DRS, PL, XPS, Raman, N2 adsorption-desorption, and CO2 adsorption characterisation data and photocatalytic CO2 reduction measurements of all the CsPbBr3 nanocrystals and CsPbBr3-Cu-RGO composites which are reported in the accepted main manuscript as well as supplementary information. Furthermore, the detailed experimental procedures for all the measurements were given in the accepted manuscript.