Boosting Reversibility of Conversion/Alloying Reactions for Sulfur-Rich Antimony-Based Sulfides with Extraordinary Potassium Storage Performance

As a new sort of energy storage device, potassium-ion batteries (PIBs) have broad application prospects in the post-lithium-ion battery era. Among the massive anode materials for PIBs, Sb-based sulfides have attracted much attention because of their high potassium storage capacity and abundant resources. However, the huge volume expansion, sluggish K+ storage kinetics, and low reaction reversibility hinder their applications. Here we composited commercial Sb2S5 with cobalt- and nitrogen-codoped carbon (CoNC) via a facile ball-milling strategy, making it an efficient anode material for PIBs. The synergistic effect between the catalysis of Co and buffering of the carbon matrix enhances the reversibility of the conversion/alloying reaction, alleviates the volume inflation, and improves the electrochemical kinetics, thus enabling the electrode to exhibit enhanced electrochemical performance. The prepared anode delivers a high reversible specific capacity (468.5 mAh g–1 at 500 mA g–1) and outstanding cycling stability (98% capacity retention after 150 cycles). In situ characterization clarified its potassium storage mechanism, and theoretical calculations revealed the reason for the improved electrochemical performance

Integrated Anodes from Heteroatoms (N, S, and F) Co-Doping Antimony/Carbon Composite for Efficient Alkaline Ion (Li⁺/K⁺) Storage

Sb-based materials are widely used in alkali metal-ion batteries due to large specific capacity, low cost, and a suitable operating voltage platform. However, they suffer from tardy dynamic performance and structural instability, along with a vague storage mechanism for alkali metal ion (Li+/K+) confining their further popularization. Herein, a scalable strategy is proposed to make Sb nanoparticles encapsulated in the N, S, and F co-doping carbon skeleton (Sb@NSF-C) with a three-dimensional ordered hierarchical porous structure. The Sb@NSF-C composite shows remarkable electrochemical performances in lithium-ion batteries (LIBs) and potassium-ion batteries (PIBs) due to improved Li+/K+ diffusion kinetics, rapid ion transport path, and stable structure. The Li+/K+ storage mechanism is detailedly investigated for the Sb@NSF-C composite. This work may provide a feasible method to design electrode materials for LIBs and PIBs with excellent performances