Nonmetallic Se/N Co‐Doped Amorphous Carbon Anode Collaborates to Realize Ultra‐High Capacity and Fast Potassium Storage for Potassium Dual‐Ion Batteries

• Published in: Advanced functional materials Vol. 34; no. 21
• Main Authors: Guan, Shuhua, Zhou, Jiwei, Sun, Shuling, Peng, Qiaoling, Guo, Xiuli, Liu, Botian, Zhou, Xiaolong, Tang, Yongbing
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.05.2024
• Subjects: amorphous carbon anode; Anodes; Carbon; Doping; Electrode materials; Nanoclusters; Nitrogen; Potassium; potassium dual‐ion batteries; Rechargeable batteries; Se/N co‐doping; Selenium; Synergistic effect; ultra‐fast potassium storage
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202314890

Heteroatom doping in carbon‐based anode materials is crucial to improve their capacity and promoting the practical application of low‐cost potassium‐ion batteries (KIBs). Herein, the selenium/nitrogen co‐doped amorphous carbon nanocluster (SeN‐ACN) anodes exhibit an ultra‐high reversible capacity of 621 mAh g−1 at 0.75 C (225 mA g−1) and a capacity retention of 93% after 2000 cycles at 5 C, which represent a remarkable achievement in potassium storage in nonmetallic doped carbon materials. This is attributed to the synergistic effects of Se/N co‐doping and their anchoring effects on potassium ions. As a proof of concept, a potassium‐based dual‐ion battery (K‐DIB), which consists of a SeN‐ACN anode and low‐cost graphite cathode, demonstrates a high reversible capacity of 118 mAh g−1 at 150 mA g−1 with a high cut‐off voltage of 5.2 V. Moreover, it presents excellent long‐term cycling performance, with 70% capacity retention after 500 cycles, among the best reported results of K‐DIBs. Thanks to the synergistic and anchoring effect of Se/N co‐doping in amorphous carbon nanoclusters, the SeN‐ACNs‐based KIB half‐cells demonstrate high capacity of 621 mAh g–1 at 0.75 C with high‐capacity retention of 93% after 2000 cycles at 5 C. Furthermore, the integration of SeN‐ACNs/EG K‐DIBs also exhibits a high capacity of 118 mAh g–1 and remarkable cycling performance.