Breaking the intrinsic activity barriers of perovskite oxides photocatalysts for catalytic CO2 reduction via piezoelectric polarization

Breaking the limitations of the intrinsic redox potential of perovskite oxides photocatalysts for catalytic CO2 reduction remains a big challenge. Here we report a new process to achieve the durability yet efficient CO2 reduction activity of various perovskite oxides (BiFeO3, LaFeO3 and LaNiO3) with an inactive CO2 photo-reduction ability via piezoelectrically polarization. Taking BiFeO3 (BFO) as a representative sample, the band tilting and structure compression of BFO reach the redox potential of CO2 reduction and build a piezoelectric field for CO2 adsorption and activation by introducing vibration energy, inducing a piezoelectric catalytic CO2 reduction process. Continued ultrasonic vibration with BFO achieves durability CO2 reduction to high production rates of CH4 (17.9 µmol g−1 h−1) and CO (28.7 µmol g−1 h−1), respectively. This crucial feature highlights the feasibility of piezoelectric catalysis for CO2 conversion by utilizing mechanical energy, which can break the limitation of intrinsic redox properties of the perovskite oxides. [Display omitted] •Piezoelectric polarization breaks the intrinsic activity barrier of perovskite oxides.•Compression of BiFeO3 builds a piezoelectric field for CO2 adsorption and activation.•Catalytic CO2 reduction is achieved at the surface of BiFeO3via piezo-polarization.•The first time to catalytic CO2 reduction by piezoelectric effect of perovskite oxides.