Activated Co in Thiospinel Boosting LiCO Decomposition in Li-CO Batteries.

Catalytic reactions mainly depend on the adsorption properties of reactants on the catalyst, which provides a perspective for the design of reversible lithium-carbon dioxide (Li-CO) batteries including CO reduction (CORR) and CO evolution (COER) reactions. However, due to the complex reaction process, the relationship between the adsorption configuration and CORR/COER catalytic activity is still unclear in Li─CO batteries. Herein, taking CoS as a model system, nickel (Ni substitution in the tetrahedral site to activate cobalt (Co) atom for forming multiatom catalytic domains in NiCoS is utilized. Benefiting from the special geometric and electronic structures, NiCoS exhibits an optimized adsorption configuration of lithium carbonate (LiCO), promoting its effective activation and decomposition. As a result, the Li-CO batteries with NiCoS cathode exhibit remarkable electrochemical performance in terms of low potential gap of 0.42 V and high energy efficiency of 88.7%. This work provides a unique perspective for the development of highly efficient catalysts in Li-CO batteries.