Sodium-selenium (Na-Se) batteries have been widely regarded as promising large-scale energy storage systems owing to the high volumetric energy density of 2530 W h L⁻¹ and natural abundance of the element sodium. However, critical drawbacks including sluggish redox kinetics, severe volume variation and shuttle effect seriously deteriorate the electrochemical performance. Herein, we propose a precompetitive coordination strategy for over-coordinated single-atom catalyst, and subsequently synthesize the six-coordinated Co electrocatalyst supported carbon nanofibers (Co-N₄C₂) for solid-state conversion in wide-temperature Na-Se batteries. The Co-N₄C₂ catalyst can not only boost the redox kinetics of solid-phase Na₂Se₂/Na₂Se, but also accelerate the electroreduction of ethylene carbonate to construct robust cathode electrolyte interphase, thereby inhibiting the irreversible phase transformation of active Se species. Furthermore, for the first time, the components of the cathode electrolyte interphase as sodium ethylene mono-carbonate are identified. Consequently, the as-synthesized free-standing Se@Co-N₄C₂ cathode with high Se-loading realizes high capacity, cycling stability and rate capability at both room temperature (20.0/40.0 ℃) and low temperature (− 11.7 ℃).

^{由于 2530 W h L -1}的高体积能量密度和元素钠的天然丰度，钠硒 (Na-Se) 电池已被广泛认为是有前途的大规模储能系统。然而，包括缓慢的氧化还原动力学、严重的体积变化和穿梭效应在内的关键缺点严重恶化了电化学性能。在此，我们提出了一种过配位单原子催化剂的预竞争配位策略，随后合成了六配位 Co 电催化剂负载碳纳米纤维 (Co-N ₄ C ₂ )，用于宽温 Na-Se 电池的固态转换. Co-N ₄ C ₂催化剂不仅可以促进固相Na ₂ Se ₂ /Na ₂ Se的氧化还原动力学，还可以加速碳酸亚乙酯的电还原以构建稳健的阴极电解质界面，从而抑制活性Se物种的不可逆相变。此外，首次确定了正极电解质中间相的成分为亚乙基单碳酸钠。因此，所合成的具有高硒载量的独立式 Se@Co-N ₄ C ₂正极在室温（20.0/40.0 ℃）和低温（− 11.7 ℃）下均实现了高容量、循环稳定性和倍率性能。 .