Ultrafast charge transfer dynamics in 2D covalent organic frameworks/Re-complex hybrid photocatalyst

• DOI: 10.1038/s41467-022-28409-2
• Publication Date: 2022-02-11T11:04:53Z
• Authors: Qinying Pan; Mohamed Abdellah; Yuehan Cao; Weihua Lin; Yang Liu; Jie Meng; Quan Zhou; Qian Zhao; Xiaomei Yan; Zonglong Li; Hao Cui; Huili Cao; Wenting Fang; David Ackland Tanner; Mahmoud Abdel-Hafiez; Ying Zhou; Tonu Pullerits; Sophie E. Canton; Hong Xu; Kaibo Zheng
• Keywords: Computational chemistry; Photocatalytic Materials for Solar Energy Conversion; Electrochemical Reduction of CO2 to Fuels; Photochemistry; Science; Chemical physics; Materials Science; Ultrafast laser spectroscopy; Organic chemistry; Laser; 02 engineering and technology; Physical Chemistry; Quantum mechanics; 7. Clean energy; Article; Catalysis; Atomic physics; Covalent bond; Electron transfer; Excited state; Materials Chemistry; Photocatalysis; Ion; Excitation; Spectroscopy; Fysikalisk kemi; Picosecond; Energy; Porous Crystalline Organic Frameworks for Energy and Separation Applications; Renewable Energy, Sustainability and the Environment; Moiety; Physics; Q; CO2 Reduction; Carbon Dioxide Capture; Optics; Materials science; Electron excitation; Chemistry; Rhenium; Physical Sciences; Photocatalysts; Heterogeneous Electrocatalysts; Density functional theory; 0210 nano-technology; Inorganic chemistry

AbstractRhenium(I)-carbonyl-diimine complexes have emerged as promising photocatalysts for carbon dioxide reduction with covalent organic frameworks recognized as perfect sensitizers and scaffold support. Such Re complexes/covalent organic frameworks hybrid catalysts have demonstrated high carbon dioxide reduction activities but with strong excitation energy-dependence. In this paper, we rationalize this behavior by the excitation energy-dependent pathways of internal photo-induced charge transfer studied via transient optical spectroscopies and time-dependent density-functional theory calculation. Under band-edge excitation, the excited electrons are quickly injected from covalent organic frameworks moiety into catalytic RheniumI center within picosecond but followed by fast backward geminate recombination. While under excitation with high-energy photon, the injected electrons are located at high-energy levels in RheniumI centers with longer lifetime. Besides those injected electrons to RheniumI center, there still remain some long-lived electrons in covalent organic frameworks moiety which is transferred back from RheniumI. This facilitates the two-electron reaction of carbon dioxide conversion to carbon monoxide.