Ming Jintao, Liu Ai, Zhao Jiwu, Zhang Pu, Huang Haowei, Lin Huan, Xu Ziting, Zhang Xuming, Wang Xuxu, Hofkens Johan, Roeffaers Maarten B J, Long Jinlin
State Key Laboratory of Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou, 350116, P. R. China.
Centre for Membrane Separation, Adsorption, Catalysis and Spectroscope for Sustainable Solutions (cMACS), KU Leuven, Celestijnenlaan 200F, 3001, Heverlee, Belgium.
Angew Chem Int Ed Engl. 2019 Dec 9;58(50):18290-18294. doi: 10.1002/anie.201912344. Epub 2019 Nov 12.
A metal-insulator-semiconductor (MIS) photosystem based on covalent organic framework (COF) semiconductors was designed for robust and efficient hydrogen evolution under visible-light irradiation. A maximal H evolution rate of 8.42 mmol h g and a turnover frequency of 789.5 h were achieved by using a MIS photosystem prepared by electrostatic self-assembly of polyvinylpyrrolidone (PVP) insulator-capped Pt nanoparticles (NPs) with the hydrophilic imine-linked TP-COFs having =C=O-H-N= hydrogen-bonding groups. The hot π-electrons in the photoexcited n-type TP-COF semiconductors can be efficiently extracted and tunneled to Pt NPs across an ultrathin PVP insulating layer to reduce protons to H . Compared to the Schottky-type counterparts, the COF-based MIS photosystems give a 32-fold-enhanced carrier efficiency, attributed to the combined enhancement of photoexcitation rate, charge separation, and oxidation rate of holes accumulated in the valence band of the TP-COF semiconductor.
设计了一种基于共价有机框架（COF）半导体的金属-绝缘体-半导体（MIS）光系统，用于在可见光照射下实现高效稳定的析氢反应。通过使用由聚乙烯吡咯烷酮（PVP）绝缘体包覆的铂纳米颗粒（NPs）与具有=C=O-H-N=氢键基团的亲水性亚胺连接的TP-COFs通过静电自组装制备的MIS光系统，实现了8.42 mmol h g的最大析氢速率和789.5 h的周转频率。光激发的n型TP-COF半导体中的热π电子可以通过超薄的PVP绝缘层有效地提取并隧穿到Pt NPs，将质子还原为H 。与肖特基型光系统相比，基于COF的MIS光系统的载流子效率提高了32倍，这归因于TP-COF半导体价带中光激发速率、电荷分离和空穴积累氧化速率的综合提高。
