光激发
共价有机骨架
材料科学
半导体
光化学
氢
化学
纳米技术
共价键
光电子学
原子物理学
有机化学
物理
激发态
作者
Jintao Ming,Liu Ai,Jiwu Zhao,Pu Zhang,Haowei Huang,Huan Lin,Ziting Xu,Xuming Zhang,Xuxu Wang,Johan Hofkens,Maarten B. J. Roeffaers
标识
DOI:10.1002/anie.201912344
摘要
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 H2 evolution rate of 8.42 mmol h-1 g-1 and a turnover frequency of 789.5 h-1 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 H2 . 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.
科研通智能强力驱动
Strongly Powered by AbleSci AI