Cu12Sb4S13 Quantum Dots/Few‐Layered Ti3C2 Nanosheets with Enhanced K+ Diffusion Dynamics for Efficient Potassium Ion Storage

• Published in: Advanced functional materials Vol. 32; no. 6
• Main Authors: Cao, Yaping, Zhang, Yelong, Chen, Hui, Qin, Shengyu, Zhang, Lanying, Guo, Shaojun, Yang, Huai
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.02.2022
• Subjects: Anodes; conversion‐type; Cu 12Sb 4S 13 quantum dots; Diffusion layers; Diffusion rate; Disulfides; Electrochemical analysis; Ion storage; Materials science; Nanosheets; Potassium; potassium‐ion batteries; Quantum dots; Rechargeable batteries; Synergistic effect; Ti 3C 2 nanosheets; Titanium
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202108574

Despite the high theoretical specific capacity of transition‐metal disulfides anode for potassium‐ion batteries (PIBs), their development has been greatly hindered by dramatic capacity fading and poor cycle life. Herein, the synthesis of the new composite of Cu12Sb4S13 quantum dots/few‐layered Ti3C2 nanosheets (CAS‐Ti3C2) as advanced anode for boosting the K ion storage is reported. It is found that as‐made CAS‐Ti3C2 show a strong synergistic effect between quantum dots and Ti3C2 nanosheets mainly caused by the formation of the Ti–S bond, which can not only shorten the diffusion path of K+ but also accommodate the serious volumetric variation during the discharge/charge process. As expected, this specially designed CAS‐Ti3C2 anode exhibits a superior reversible specific capacity of 496.7 mAh g−1 at 100 mA g−1 after 200 cycles and 175.6 mAh g−1 at a high current density of 1.0 A g−1 even over 1800 cycles, preceding most of the reported transition‐metal disulfides quantum dots‐based anodes for PIBs. These comprehensive studies reveal that the excellent electrochemical property is attributed to the fast K+ diffusion kinetics and unique transformation and restorage mechanism between K+ with CAS‐Ti3C2 anode. A class of CAS‐Ti3C2 composites with excellent electrochemical performances is reported as an advanced nanostructured electrode for potassium ion batteries (PIBs). The strong synergistic interaction between the Cu12Sb4S13 quantum dots and few‐layered Ti3C2 nanosheets endows the hybrid electrode with a high conductivity network, robust structural stability, and short K+ diffusion path for boosting the capacity, rate ability, and stability of PIBs.