Atomically‐Dispersed Fe‐N4 on 3D Hierarchical Porous Carbon for High‐Performance Lithium‐Sulfur Battery.

Lithium‐sulfur (Li−S) battery with the advantages of high theoretical capacity and low cost is a promising technology for advanced energy storage. However, poor conductivity of the sulfur cathode, huge volume expansion, shuttling effect and sluggish catalytic conversion of lithium polysulfide hinder its commercialization. Herein, a 3D hierarchical porous carbon loaded with atomically dispersed Fe‐N4 was developed as a sulfur cathode, which not only offers enhanced electronic conductivity, but also alleviates volume expansion. Moreover, density functional theory calculation results suggest that the Fe‐N4 sites are favorable to enhance the diffusion and promote the conversion of lithium polysulfide. Consequently, lithium‐sulfur battery with 3D hierarchical porous carbon as the sulfur cathode exhibit good capacity and cycling performance, where a high initial specific capacity of 1289.3 mAh g−1 can be delivered at 0.1 C, and a capacity loss of only 0.025 % per cycle can be achieved for 1000 cycles at 2.0 C. [ABSTRACT FROM AUTHOR]