Anchoring Unique Bi ₂ Te ₃ ‐BiPO ₄ Heterostructure on Porous N, S co‐Doped Carbon Nanorods for Advanced Zn‐Ion Batteries

Abstract The topological insulator Bi 2 Te 3 has garnered significant interest in zinc‐ion batteries (ZIBs) due to its unique quantum effects and substantial theoretical capacity. However, challenges arise from issues such as volume expansion and sluggish dynamic behavior. Herein, Bi‐1,3,5‐benzenetricarboxylic acid (Bi‐BTC) nanorods are prepared via solvothermal method, to boost the structural stability, the Bi‐BTC nanorods are successfully coated with a polyphosphazene layer (denote as Bi‐BTC@PZS), and the topological insulator Bi 2 Te 3 ‐BiPO 4 heterostructured nanoparticles embedded in N, S‐doped carbon nanorods (Bi 2 Te 3 ‐BiPO 4 @NSC) are obtained through tellurization in N 2 gas. Experimental studies coupled with theoretical calculations prove that the design of Bi 2 Te 3 ‐BiPO 4 @NSC heterojunction with a built‐in electric field enhances the intrinsic conductivity and accelerates the ion adsorption ability, leading to improved electrochemical kinetics and remarkable stability in both morphological and structural. The electrochemical storage mechanism reveals co‐insertion of Zn 2+ /H + with enhanced adsorption energy attributed to the incorporation of BiPO 4 . These enhancements result in a substantial specific capacity of 458.2 mAh g −1 at 0.2 A g −1 , high‐rate performance, and reliable cycling stability. The assembled flexible quasi‐solid‐state battery demonstrates robust mechanical stability and practical viability under‐folding state. This work offers valuable insights into the topological insulator cathode for high‐performance, safety, and stability.