A Liquid Metal‐Enabled Catalyst for Li‐CO2 Battery

A liquid metal-based catalyst with high electrical conductivity and efficient catalysis, anchored on reduced graphene oxide, referred to as rGO@LM@Ru, is proposed as the cathode for reversible Li-CO₂ battery. The composite cathode can significantly alleviate passivation of Li₂CO₃ and enhance the CO₂ evolution reaction  catalytic efficiency, thereby enable a high-efficiency and long-term stable energy storage system.

Abstract

Lithium-carbon dioxide (Li-CO₂) batteries have recently emerged as an innovative solution for energy storage and CO₂ capture, storage, and utilization. However, Li-CO₂ chemistry exhibits poor reversibility and limited cycle life due to the cathode passivation caused by insulating discharge product—Li₂CO₃. Herein, a liquid metal (LM)-based catalyst anchored on reduced graphene oxide (rGO@LM@Ru) is introduced to mitigate cathode passivation and thus enhance the electrochemical performance of Li-CO₂ batteries. These findings indicate that LM plays a critical role in improving charge transfer and stabilizing the Ru catalyst on its surface. The rGO@LM@Ru cathode offers a low charge/discharge voltage gap of 1.0 V, an extended cycle life over 500 h, as well as enhanced capacity and rate performance for Li-CO₂ batteries. This work proposes a novel cathode design for CO₂ redox, which suggests the promising application of the LM for next-generation batteries.