Synthesis of CoSe 2 reinforced nitrogen-doped carbon composites as advanced anodes for potassium-ion batteries

• Published in: Inorganic chemistry frontiers Vol. 9; no. 15; pp. 3719 - 3727
• Main Authors: Yang, Guowei, Yan, Chengzhan, Hu, Ping, Fu, Qun, Zhao, Huaping, Lei, Yong
• Format: Journal Article
• Language: English
• Published: 26.07.2022
• ISSN: 2052-1553; 2052-1553
• DOI: 10.1039/D2QI00848C

Potassium-ion batteries (PIBs) are considered potential candidates for large-scale energy storage applications with cost superiority. However, the development of PIBs is severely restricted by the sluggish electrochemical kinetics and severe volume expansion of anode materials. Herein, CoSe 2 reinforced nitrogen-doped carbon composites (CoSe 2 @C) are synthesized via a simple solution-based etching-coating method and further studied as high-performance anodes for PIBs. Electrochemical characterization studies indicate that the potassium storage performance of CoSe 2 @C composite anodes relies on the initial mass ratio of CoSe 2 nanosheets and carbon precursors (that is dopamine hydrochloride) during the synthesis process. In the case of the mass ratio of CoSe 2 nanosheets and dopamine hydrochloride being 1 : 1, the as-obtained CoSe 2 @C-1 : 1 anode exhibits a high reversible capacity (366.1 mA h g −1 at 0.1 A g −1 after 100 cycles), an excellent long-cycle stability (237.6 mA h g −1 at 1.0 A g −1 after 1000 cycles), and a good rate capability (281.5 mA h g −1 at 5.0 A g −1 ). The optimum performance of CoSe 2 @C-1 : 1 as a PIB anode in terms of cycling stability and kinetics is attributed to the uniform distribution of CoSe 2 nanoparticles inside the carbon matrix.