Piezoelectric effect-assisted Z-scheme heterojunction ZnIn2S4/BaTiO3 for improved photocatalytic reduction of CO2 to CO

Converting CO2 into high-value-added chemicals by artificial photosynthesis technology effectively solves environmental problems and energy shortages. Nevertheless, it remains challenging to improve CO2 conversion rates due to low photo-utilization and rapid electron-hole recombination. In this study, we successfully synthesized direct Z-scheme ZnIn2S4/BaTiO3 heterojunction structure by a hydrothermal method. Specifically, compared with previous studies of various heterojunction catalysts, ZnIn2S4/BaTiO3 heterojunction structure achieved a remarkably high yield of 105.89 μmol g-1 h-1, increasing 2.55 and 3.62-fold over the individual performance of ZnIn2S4 and BaTiO3, respectively. Our investigation of photocatalytic mechanism suggest that the improved photocatalytic CO2 reduction performance can be attributed to the synergistic effects of the piezoelectric effect and Z-scheme electron transfer mechanism. These effects can synergistically enhance space charge separation and retain photogenerated electrons, thereby facilitating a more efficient CO2 reduction process. Consequently, this innovative piezoelectric effect-assisted Z-scheme heterojunction demonstrates immense potential to offer a novel strategy for addressing CO2 reduction challenges and advancing sustainable energy development.