Abstract
Photocatalysis is an important means of realizing the efficient use of solar energy and alleviating energy consumption and environmental pollution. This work used a simple solvothermal synthesis method to prepare a series of zinc sulfide/sulfur-doped polyimide (ZnS/SPI) direct Z-type heterostructured photocatalysts. ZnS/SPI heterostructured photocatalysts have better photogenerated electron-hole pairs separation and wider visible light absorption region. The effect of ZnS on the properties of ZnS/SPI composites, such as morphology, structure, and optoelectronic properties, was systematically investigated by a series of characterization tests. These results showed that the photocatalytic activity of the ZnS/SPI composite was significantly improved compared with SPI. The 10ZnS/SPI composite exhibited the highest photocatalytic hydrogen production rate under full irradiation (216.9 µmol/g/h), which was about 2.8 times higher than that of SPI (76.6 µmol/g/h). Moreover, it has a high stability over a long period in the photocatalytic process. The enhanced photocatalytic performance of the ZnS/SPI heterojunction is mainly due to the close contact between the ZnS nanoparticles and the SPI interface, which improves the charge separation and reduces the complexation rate of electron-hole. This work shows that the formation of ZnS/SPI composites Z-type heterojunction can effectively enhance the activity of polymer photocatalysts.