Frustrated Lewis Pair Sites Boosting CO2 Photoreduction on Cs2CuBr4 Perovskite Quantum Dots

Lead (Pb) halide perovskite quantum dots (PQDs) are promising candidates for the photochemical reduction of CO2. However, the intrinsically weak adsorption and activation toward inert CO2 molecules have seriously hindered their practical application. This study reports alternative Cs2CuBr4 PQDs for gas–solid phase photocatalytic CO2 reduction under simulated solar irradiation. Cs2CuBr4 PQDs exhibited CO2 photoreduction performance with CH4 and CO yields of 74.81 and 148.98 μmol g–1, respectively. In situ diffuse reflectance infrared Fourier transform spectra and density functional theory calculations cooperatively revealed the synergistic strengthening of microelectronic polarization in Cs2CuBr4 PQDs induced by surface-frustrated Lewis pair-like properties and intrinsic Cu d-band properties facilitated robust CO2 adsorption and activation. This study demonstrated the potential of Cs2CuBr4 PQDs as a platform for highly efficient CO2 photoreduction and provided a distinct concept for CO2 adsorption and activation based on the catalytic mechanism of Cu-based PQDs.