3D Array of Bi2S3 Nanorods Supported on Ni Foam as a Highly Efficient Integrated Oxygen Electrode for the Lithium‐Oxygen Battery

Bismuth sulfide nanorod array is directly grown on nickel foam (R‐Bi₂S₃/NF) to serve as a completely carbon and binder‐free 3D porous oxygen electrode material for lithium‐oxygen (Li‐O₂) batteries. The synergistic effect of the fast kinetics of electron transport and gas and electrolyte diffusion provided by the continuous free‐standing network structure and the excellent electrocatalytic activity of the bismuth sulfide nanorod array enables outstanding performance of the oxygen electrode. Li‐O₂ battery with the free‐standing R‐Bi₂S₃/NF oxygen electrode exhibits high energy efficiency (78.7%), good rate capability (4464 mA h g⁻¹ at 1500 mA g⁻¹), as well as excellent cyclability (146 cycles) while maintaining a moderate specific capacity of 1000 mA h g⁻¹. The effect of cathodes with different reactant (O₂) and intermediate (LiO₂) adsorbability on the product (Li₂O₂) growth model is studied by first‐principle calculations. The strong O₂ adsorption and weak LiO₂ adsorption on Bi₂S₃ drives the growth of large‐size Li₂O₂ particles via solution growth model. Remarkably, the large‐area pouch‐type Li‐O₂ battery delivers an energy density of 330 Wh kg⁻¹. The present results open up a promising avenue toward developing novel electrode architecture for high‐performance Li‐O₂ batteries through controlling morphology and functionality of porous electrodes.