Understanding the synergistic effect of piezoelectric polarization and the extra electrons contributed by oxygen vacancies on an efficient piezo-photocatalysis CO₂ reduction

Global climate is facing an unprecedented challenge due to greenhouse gases. Fortunately, piezoelectric catalysis can promote the performance of photocatalysis to reduce CO2, making the efficiency of using piezo-photocatalysis to reduce CO2 better than that of piezoelectric catalysis and photocatalysis. This work focuses on the synthesis of oxygen vacancy regulated BiFeO3 (BiFeO3-x) for the reduction of CO2 by piezo-photocatalysis. When the piezo-photocatalysis time is 9 h, the yields of CO2 reduction to CO and CH4 reach as high as 142.6 mu mol g(-1) and 32.8 mu mol g(-1), respectively. This result is benefited by the synergistic effect of piezoelectric polarization and the extra electrons contributed by oxygen vacancies. Meanwhile, the oxygen vacancies also greatly improve the performance of the piezo-photocatalysis reduction of CO2. This work may open a new window and provides new ideas for CO2 reduction by piezo-photocatalysis.