Enhanced photocatalytic hydrogen generation over a Z-scheme nanohybrid composed of porphyrin cobalt metal-organic frameworks in-situ fabricated on potassium niobate microflowers

Abstract

A promising direct Z-scheme KNO MF/Co-PMOF nanohybrid was facilely achieved by cobalt meso-tetrakis(4-carboxyphenyl) porphyrin metal organic frameworks (Co-PMOF) in-situ grown on potassium niobate microflowers (KNO MF). The tight combination of the two semiconductors can be confirmed by HRTEM. It was found that the spectral range can be effectively expanded, and also the carrier separation and migration efficiency in the nanohybrid can be effectively improved by the establishment of the built-in electric field at the interface. Under irradiation without adding any cocatalysts, the optimized KNO MF/Co-PMOF exhibited 14.5 times higher activity than that of pristine KNO MF. Moreover, the KNO MF/Co-PMOF showed a good durability in five continuous recycles (30 h). This study will provide a promising strategy for designing Z-type photocatalysts for enhanced H2 release.