Redox Molecular Junction Metal‐Covalent Organic Frameworks for Light‐assisted CO2 Energy Storage

Abstract

AbstractVisible‐light sensitive and bi‐functionally favored CO2 reduction (CRR)/evolution (CER) photocathode catalysts that can get rid of the utilization of ultraviolet light and improve sluggish kinetics is demanded to conquer the current technique‐barrier of traditional Li‐CO2 battery. Here, a kind of redox molecular junction sp2c metal‐covalent organic framework (i.e. Cu3‐BTDE‐COF) has been prepared through the connection between Cu3 and BTDE and can serve as efficient photocathode catalyst in light‐assisted Li‐CO2 battery. Cu3‐BTDE‐COF with redox‐ability, visible‐light‐adsorption region, electron‐hole separation ability and endows the photocathode with excellent round‐trip efficiency (95.2 %) and an ultralow voltage hysteresis (0.18 V), outperforming the Schiff base COFs (i.e. Cu3‐BTDA‐COF and Cu3‐DT‐COF) and majority of the reported photocathode catalysts. Combined theoretical calculations with characterizations, Cu3‐BTDE‐COF with the integration of Cu3 centers, thiazole and cyano groups possess strong CO2 adsorption/activation and Li+ interaction/diffusion ability to boost the CRR/CER kinetics and related battery property.