The PZT/Ag2O heterostructure for synchronous pyrocatalytic-photocatalytic towards efficient degradation of pollutants through integration of solar and thermal energy

Charge separation and transport as well as light absorption are pivotal in determining the efficiency of dye degradation. Here, we designed a PZT/Ag2O heterostructure to improve the degradation of dye by chemical precipitation method. The carrier separation process of Z-scheme heterojunction and the promotion effect of pyroelectric polarization on the performance of PZT/Ag2O heterojunction are discussed in detail. Under 20–55 °C temperature cycle and visible light irradiation, PZT/1.5Ag2O with bi-catalysis could degrade up to 93.7% of RhB within 140 min. It was 3.38 times and 1.51 times higher than bi-catalysis degradation rate of PZT (27.78%) and Ag2O (61.97%) alone, respectively. The improvement of catalytic efficiency is due to the enhanced light response range of the PZT/Ag2O heterojunction, while the pyroelectric polarization further promotes carrier separation and transfer. In addition, we found an interesting phenomenon of increased hydrophilicity of the composite, which may also be one of the reasons for its improved performance. The concept of PZT/Ag2O heterostructure pyro-photo-catalyst provides an effective way to utilize solar energy and thermal energy.