Tension-strained mesoporous Pt nanosheets for Li‒CO₂ batteries with low overpotential

The slow kinetics of the cathode CO₂ reduction reaction and the decomposition reaction of Li₂CO₃, a wide-bandwidth insulating product, lead to difficult CO₂ capture and high charging potential in Li‒CO₂ batteries. To improve the reaction kinetics and decrease the reaction overpotential, we synthesized mesoporous Pt nanosheets with high tensile strain. The presence of many unsaturated coordinated Pt atoms around the pores gives rise to tensile strain in the mesoporous Pt nanosheets. This tensile strain plays a key role in regulating the interactions between the catalytic surface of Pt and the adsorbed intermediates. The two-dimensional structure provides more active sites on the surface for the catalytic reactions. These superiorities enable a low overpotential of 0.36 V at a cutoff capacity of 100 μAh·cm⁻² at a current density of 10 μA·cm⁻² over more than 2000 h. This study opens new possibilities for the rational design of metal-based materials with strain engineering for electrochemical energy storage.