Electrochemical performance of CoSe2 with mixed phases decorated with N-doped rGO in potassium-ion batteries. Issue 33 (2nd August 2022)

• Record Type: Journal Article
• Authors: Zheng, Hui; Xu, Han-Shu; Hu, Jiaping; Liu, Huimin; Wei, Lianwei; Wu, Shusheng; Li, Jin; Huang, Yuhu; Tang, Kaibin
• Is Part Of: RSC advances. Volume 12:Issue 33(2022)
• Page Start: 21374
• Page End: 21384
• Publication Date: 2022-08-02
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d2ra03608h
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Potassium-ion batteries (PIBs) have received much attention as next-generation energy storage systems because of their abundance, low cost, and slightly lower standard redox potential than lithium-ion batteries (LIBs). Abstract : Potassium-ion batteries (PIBs) have received much attention as next-generation energy storage systems because of their abundance, low cost, and slightly lower standard redox potential than lithium-ion batteries (LIBs). Nevertheless, they still face great challenges in the design of the best electrode materials for applications. Herein, we have successfully synthesized nano-sized CoSe2 encapsulated by N-doped reduced graphene oxide (denoted as CoSe2 @N-rGO) by a direct one-step hydrothermal method, including both orthorhombic and cubic CoSe2 phases. The CoSe2 @N-rGO anodes exhibit a high reversible capacity of 599.3 mA h g −1 at 0.05 A g −1 in the initial cycle, and in particular, they also exhibit a cycling stability of 421 mA h g −1 after 100 cycles at 0.2 A g −1 . Density functional theory (DFT) calculations show that CoSe2 with N-doped carbon can greatly accelerate electron transfer and enhance the rate performance. In addition, the intrinsic causes of the higher electrochemical performance of orthorhombic CoSe2 than that of cubic CoSe2 are also discussed.