Tellurium-based potassium-ion batteries: design strategies, challenges, and prospects for emerging electrode materials

Potassium ion batteries (PIBs) have attracted widespread attention due to their higher power density, low operating voltage, wide temperature range adaptability and cost effectiveness. Nevertheless, the practical application of PIBs remains hindered by several critical challenges, including limited specific capacity, poor cycling stability, and severe volume expansion of electrode materials. Among various candidate electrode materials, tellurium-based materials exhibit significant application potential in PIBs owing to their outstanding electronic conductivity, high theoretical specific capacity, and unique structural characteristics. This review systematically summarizes recent research progress on elemental tellurium, telluride, tellurium compounds, and tellurium-doped materials in the context of PIBs electrode. Furthermore, the electrochemical performance, potassium storage mechanisms and structural evolution processes of these materials are comprehensively analyzed. In particular, modulation strategies including morphology control, composite structures, and defect engineering have been shown to be effective in enhancing the cycling durability, rate capability and K + diffusion rate of tellurium-based electrode materials. Eventually, the key issues and technical bottlenecks currently faced by tellurium-based materials in PIBs are discussed, and future development directions along with potential engineering applications are envisioned. This review aims to provide a theoretical foundation and guidance for the development of high performance PIBs electrode materials. This manuscript offers an in-depth analysis of Te-based materials for PIBs, emphasizing the structural properties and potassium-ion storage mechanisms of various Te-based electrode materials. It further explores the challenges these materials face and examines key optimization strategies, including morphology control, defect mechanism and composite structure development, while assessing the effectiveness and applicability of each method in enhancing electrochemical performance. • The potassium storage mechanism of Te-based materials in PIBs is outlined. • The advantages, challenges and modifications of Te-based materials are summarized. • Explores the future development and technological breakthroughs of Te-based PIBs.