Localized surface plasmon resonance-interface induces ultrafast hot-electron spatiotemporal transfer for boosting photocatalytic H2 evolution integrated with benzylamine C-N coupling

Abstract

Effective spatiotemporal transfer of electrons/holes is essential for enhancing photocatalytic performance. Plasmonic heterojunction structures can expedite electron transfer to timescales as short as hundreds of femtoseconds. However, the process faces a formidable challenge in hot-electron self-thermalization (100 fs~1ps), which leads to energy loss of photogenerated carriers. Therefore, it is urgent to develop appropriate catalyst structures for ultrafast electron/hole separation and transfer. Herein, we proposed that constructing localized surface plasmon resonance (LSPR)-interface structures that enable ultrafast hot-electron transfer for boosting photocatalysis. Taking MoO3-x@ZnIn2S4 as the example, this plasmonic heterojunction forms an interfacial Mo-S bond with π surface plasmon mode, which can produce a near-field enhancement effect at the interface and suppress the decay of hot-electrons. Then the strong interfacial Mo-S bonding can be served as the unique channel to enable the ultrafast hot-electron separation and transfer from MoO3-x into ZnIn2S4. And ultimately the efficient spatiotemporal separation of electrons and holes in MoO3-x@ZnIn2S4 boosted photocatalytic H2 evolution integrated with benzylamine C-N coupling with the yields of H2 and C-N coupling products reaching 52.35 and 21.98 mmol g-1 h-1, respectively. This study not only provides a successful paradigm of constructing LSPR-interface to realize ultrafast hot-electron direct transfer and spatiotemporal separation for enhancing the overall photocatalytic activity, but also opens a new horizon to design novel photocatalyst structures for cooperative photoredox systems.