Enhanced pyro-/photo catalysis of the pyroelectric PZT/CdS heterostructure for dye decomposition driven by visible light and cold-hot cycles

Abstract

Semiconductor heterojunction have received wide attention for their enhanced catalytic properties. In this paper, the PZT/CdS pyroelectric heterojunction prepared by hydrothermal method has remarkable pyro-/photo catalytic degradation performance and RhB can be almost completely degraded within 120 min. The pyro-/photo catalytic degradation of RhB by PZT/CdS was 99.25% under 20–55 °C and visible light irradiation, which was 1.5 times and 6 times that of PZT/CdS (64.72%) and PZT (16.35%) photocatalysis, respectively. The increase of decomposition rate is because the introduction of CdS not only expands the light response range of the material, but also improves the redox ability of the material. At the same time, CdS and PZT can also produce pyroelectric effect under temperature fluctuation. Double pyroelectric effect and heterojunction work together to further promote the separation of carriers. This study confirmed that PZT/CdS heterojunctions based on pyroelectric effect can achieve efficient pyro-/photo catalysis by using solar/thermal energy, which provides a reference in the field of catalytic degradation of dye wastewater by multiple energy sources.