Quantum Dot/ZIF-67/ZIF-8 Heterostructure for Efficient Photocatalytic Hydrogen Production

Abstract

With a high porosity and highly adaptable topology, ZIF-67 is considered the most promising photocatalyst and has received much attention and development. However, the photoactive electron extraction rate of ZIF-67 is still low, which is a major problem limiting its further development. In this paper, based on the type I structure and using quantum dots (QDs) as the active site, we obtain the QDs@ZIF-67/ZIF-8 heterostructure, which ensures high-yield hydrogen efficiency. Quantum dots, as the transmission site of photogenerated electrons, improve the photogenerated carrier utilization rate generated by the strong absorption ability of ZIF-67 in the visible-light region. Through careful characterization, it was found that the optimal photocatalytic rate of 4999.7 μmol·g–1·h–1, a value 30 times higher than that of QDs, provides an innovative band gap-matching design for adjusting the charge transfer characteristics of QDs with a narrow band gap, which realizes the efficient utilization of visible light.