Enhancement of piezophototronic hydrogen evolution reaction through the polarization of ferroelectric Bi4Ti3O12 microplates.

In this study, we analyzed the properties of Bi 4 Ti 3 O 12 microplates in the context of hydrogen evolution reaction. Piezoresponse force microscopy revealed a typical butterfly curve, indicating that as-synthesized Bi 4 Ti 3 O 12 exhibits ferroelectric properties. Under ultrasonication, the amount of hydrogen produced by polarized (2000 V) Bi 4 Ti 3 O 12 increased from 728 to 1349 μmol g−1, which was 1.85 times higher than that generated by unpolarized Bi 4 Ti 3 O 12. The increase in hydrogen evolution rate may be attributed to the gradual alignment of polarization within the ferroelectric domains of Bi 4 Ti 3 O 12. Moreover, with synergistic piezophototronic activity, the amount of hydrogen produced by Bi 4 Ti 3 O 12 was further increased to 1478 μmol g−1, which was 200% higher than that generated by unpolarized Bi 4 Ti 3 O 12. Theoretical calculations revealed that Bi 4 Ti 3 O 12 microplates exhibit a high piezoelectric potential along the x - axis, which is consistent with the spontaneous polarization of the microplates. By applying an external polarization field, ferroelectric polarization was activated to effectively separate free charges and extend carrier lifetime (from 0.6 to 0.84 ns). The application of an external electric field to ferroelectric Bi 4 Ti 3 O 12 appears to be a favorable strategy for enhancing its piezophototronic activity. Our findings may facilitate future studies in the fields of environmental science and renewable energy. The theoretical calculation demonstrated that Bi 4 Ti 3 O 12 microplates exhibit a high piezoelectric potential along the x - axis, which is consistent with the spontaneous polarization of Bi 4 Ti 3 O 12 microplates. By applying an external field of poling treatment, ferroelectric polarization could be activated to separate free charges and prolong carrier lifetime effectively from 0.6 to 0.84 ns, producing H 2 gas of 1478 μ m o l · g − 1 through piezophotronic process. [Display omitted] • Enhanced Piezophototronic catalytic Hydrogen Evolution Reaction by the applied electric field to Bi 4 Ti 3 O 12 microplates. • With synergistic piezophototronic activities, hydrogen generation enhanced to 1478 μ m o l · g − 1 , 200% higher than that of unpoled Bi 4 Ti 3 O 12. • Applying an external poling treatment field and prolonging carrier lifetime effectively from 0.6 to 0.84 ns. [ABSTRACT FROM AUTHOR]