Electronic Localization Modulation of the Cyano‐Bridged Cu3[Co(CN)6]2 Catalyst With Heterometallic Active Sites for High‐Performance Li‐CO2 Batteries

Cyano-bridged CoCu heterometallic sites (CoCuCN) with tailored electronic localization are designed and demonstrated as an appealing catalyst for lithium-carbon dioxide (Li-CO₂)batteries. Synergistic 3d orbital modulation and enhanced charge transfer enable efficient CO₂ conversion and high-performance Li-CO₂ battery with a long lifespan of 1480 h and a low overpotential of 1.18 V.

Abstract

Lithium-carbon dioxide (Li-CO₂) batteries represent an emerging and promising technology that combines energy storage with environmental sustainability by effectively capturing and converting CO₂. However, the sluggish electrochemical reaction kinetics and excessive accumulation of the discharge product with low conductivity at the cathode always lead to large polarization and limited lifespan of the battery. Herein, a new cyano-bridged heterometallic active site catalyst (Cu₃[Co(CN)₆]₂) is proposed to augment CO₂ transformation reaction kinetics through electronic localization modulation. Computational simulation and series experiments confirm that the asymmetric electronic distribution in the cyano-bridge promotes distinct electron transfer, which significantly improves the CO₂ adsorption ability and catalytic activity of the Co active site with the assistance of the Cu active site, contributing to a remarkable efficiency in driving the CO₂ reduction and simultaneously facilitates CO₂ evolution reactions. Consequently, the assembled Li-CO₂ batteries manifest attractive cycling stability exceeding 1480 h with a low overpotential of 1.18 V at 300 mA g⁻¹, exhibiting appealing competition with the previously reported work. This work offers an ingenious insight into designing low-cost dual-metal site catalysts for advanced Li-CO₂ batteries.