Enhanced charges separation to improve hydrogen production efficiency by organic piezoelectric film polarization

Using the polarization field by piezoelectric materials was a promising technique to improve the photoinduced charges separation. In this study, PVDF-BaTiO3-Cd0.9Zn0.1S (PVBC) flexible composite films were synthesized via a spin-coating method. The composite films were detailed characterized by XRD, SEM, XPS, DRS and PFM. Based on the experimental results, the polarization field generated by the piezoelectric PVDF and BaTiO3 effectively enhanced the charge separation of the composite film, resulting in improved photocatalytic H2 evolution performance. The optimal PVBC film exhibited the best H2 evolution rate of 231.39 μmol/h, which was about 4.48 times higher than PVDF-Cd0.9Zn0.1S film. In addition, we proposed a plausible mechanism for the enhanced photocatalytic activity. In a wider perspective, this work provided an efficient strategy, combining solar energy with electric energy induced by organic flexible piezoelectric PVDF, to remarkably improve activity of photocatalysts.