The aprotic Li-CO₂ battery with high energy density is an attractive energy-storage technology. However, its development is largely impeded by the sluggish kinetics of CO₂ reduction and evolution reactions. Here, we demonstrate a class of ultrathin triangular RuRh alloy nanosheets as an exceptionally active catalyst for greatly accelerating the kinetics of CO₂ reduction and evolution reactions and achieving a high-performance Li-CO₂ battery. The RuRh alloy nanosheets-based battery can achieve the lowest voltage gap of 1.35 V during the charge-discharge process and stably cycle for 180 cycles with a cutoff capacity of 1,000 mAh g⁻¹ at 1,000 mA g⁻¹. Density functional theory calculations demonstrate the pivotal roles of Rh introduction in RuRh alloy nanosheets, which evidently activate the electron-transfer ability of surface Ru and balance the CO₂ binding near Ru sites. We find that the d-d correlation between Rh and Ru contributes to the energetically favorable cycle of the Li-CO₂ battery.

具有高能量密度的非质子Li-CO ₂电池是一种有吸引力的能量存储技术。然而，CO ₂还原和析出反应的缓慢动力学极大地阻碍了其发展。在这里，我们展示了一类超薄三角形RuRh合金纳米片，作为一种极活泼的催化剂，可极大地加速CO ₂还原和析出反应的动力学并实现高性能的Li-CO ₂电池。RuRh合金纳米片基电池可在充电和放电过程中实现1.35 V的最低电压间隙，并在1,000 mA g ^-1时的截止容量为1,000 mAh g ^-1的情况下稳定循环180个循环。密度泛函理论计算证明了Rh引入RuRh合金纳米片中的关键作用，这显然激活了表面Ru的电子转移能力并平衡了Ru部位附近的CO ₂结合。我们发现，Rh和Ru之间的dd相关性有助于Li-CO ₂电池在能量上有利的循环。