Homonuclear transition-metal dimers embedded monolayer C2N as promising anchoring and electrocatalytic materials for lithium-sulfur battery: First-principles calculations同核过渡金属二聚体嵌入单层C2N作为锂硫电池的有前途的锚定和电催化材料: 第一性原理计算APPLIED SURFACE SCIENCEIF6.92023-02-0116PRE