Photoactive Zeolitic Imidazolate Framework as Intrinsic Heterogeneous Catalysts for Light-Driven Hydrogen Generation

Abstract

Zeolitic imidazolate frameworks (ZIFs) with intrinsic photoactivity represent an excellent scaffold for a single-site photocatalytic center. However, their application in visible-light-driven photocatalysis is hampered by their light-harvesting ability due to limited coverage in the realm of the solar spectrum and relatively low extinction coefficient. In this work, we report the first example of the enhanced light-harvesting property of ZIF-67 via energy transfer from a molecular photosensitizer, that is, the RuN3 complex, sensitized on the surface of ZIF-67. Using transient absorption spectroscopy, we show that energy transfer occurs from the excited RuN3 to ZIF-67 with ∼86.9% efficiency. More importantly, this RuN3/ZIF-67 hybrid system exhibits significantly enhanced photocatalytic activity for H2 production from water, which can be attributed to efficient energy transfer from RuN3.