Phosphorus‐Tuned Nickel Boride Nanocatalyst with Enhanced p–p Interaction for Expediting Sulfur Electrochemistry in Lithium‐Sulfur Batteries

Abstract Rationally modulating the electronic structure of sulfur electrocatalysts is essential for the development of reliable lithium–sulfur (Li–S) batteries. Herein, a phosphorus‐doping strategy is presented to finely tune the electronic properties of nickel boride (P‐NiB), facilitating highly efficient sulfur electrocatalysis. Through a combination of theoretical modeling and experimental validation, It is demonstrated that the electronegative P reduces the occupancy of B 2p orbitals, promoting B─S bonding via enhanced p‐p orbital interaction. Meanwhile, P and Ni atoms also exhibit strong affinities to polysulfides via p‐p and p‐d interactions, respectively, rendering a globally sulphophilic catalyst that effectively confines polysulfides and lowers conversion energy barriers. This leads to fast and durable sulfur redox reactions, with P‐NiB‐based Li–S cells outperforming their undoped NiB and bare carbon counterparts in both cyclability (1000 cycles) and rate capability (5 C). Furthermore, a high areal capacity of up to 8.94 mAh cm⁻² is achieved under high‐loading and lean‐electrolyte conditions, along with the demonstration of a multi‐layered pouch cell delivering a high overall capacity of 1.2 Ah. This work highlights an efficient anion‐tuning strategy for optimizing metal boride‐based sulfur electrocatalysis, offering a promising pathway toward high‐performance and practically viable Li–S batteries.