Construction of a MAPbBr3/BiFeO3 Z-scheme heterojunction with enhanced piezo-photocatalytic performance

Based on the large visible light absorption coefficient and tunable band gap of MAPbBr(3), weakening the strong photogenerated carrier recombination tendency to exploit the CO2 reduction potential is a worthy research topic. The built-in polarized electric field induced by the piezoelectric effect can guide the directional movement of charged particles, which is considered to be an effective driving force for the separation of electron-hole pairs. In this work, a MAPbBr(3)/BiFeO3 Z-scheme heterojunction was prepared by a simple mechanical synthesis method, which showed an enhanced CO2 reduction performance where the optimal sample (MB1) achieved yields of 8.4 mu mol g(-1) (CH4) and 3.7 mu mol g(-1) (CO) under light alone as well as 4.1 mu mol g(-1) (CH4) and 1.7 mu mol g(-1) (CO) under ultrasound alone, thanks to the improved separation rate of photogenerated carriers due to the construction of the MAPbBr(3)/BiFeO3 Z-scheme heterojunction. Moreover, MB1 had a CH4 yield of 34.9 mu mol g(-1) and a CO yield of 15.1 mu mol g(-1) under the dual energy drive system of illumination and piezoelectricity, which are 6.7 and 5.6 times higher than the original MAPbBr(3), respectively.