MnCr2O4/graphene composite as a high-performance anode material for lithium-ion batteries

• Published in: Electrochimica acta 2021-03, Vol.372, p.137855, Article 137855
• Main Authors: babu, G.N. Suresh, Kalaiselvi, N.
• Format: Article
• Language: English
• Subjects: Anode; Anode effect; Chromium; Cycles; Electrochemical analysis; Electrode materials; Graphene; Graphite; Lithium; Lithium-ion batteries; Metal oxides; Microstructure; Post cycling; Rate capability; Rechargeable batteries; Structural integrity; Synergistic effect
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2021.137855

•MCO/G composite is prepared by a simple and scalable solid-state route.•MCO/G anode delivers an appreciable capacity of 1794 mAh g−1 with excellent capacity retention.•MCO/G demonstrates excellent rate capability at 1 A g−1 with a capacity of 402 mAh g−1.•Mechanical and structural integrity of the MCO/G electrode are encouraging. A simple, facile and scalable solid-state reaction technique is adopted to obtain phase pure MnCr2O4 (MCO), which is further embedded on graphene sheets to make MnCr2O4/Graphene (MCO/G) composite. As an anode for lithium ion batteries, for the first time, MnCr2O4/Graphene (MCO/G) composite exhibits a high reversible specific capacity of ̴ 1794 mAh g−1 (5 times higher than the theoretical capacity of graphite) at 50 mA g−1 for 100 cycles, along with a Coulombic efficiency of 99%. Further, a capacity of around 402 mAh g−1 is obtained at a high current density of 1 A g−1, which is still significantly higher than the capacity of graphite. The impressive electrochemical performance of MnCr2O4/Graphene (MCO/G) composite could be attributed to the effective alleviation of huge volume changes by graphene during cycling and the synergistic effect between the Mn and Cr mixed metal oxides. Furthermore, chemical, mechanical and structural integrity of the MnCr2O4/Graphene (MCO/G) composite anode have been validated using series of post-mortem analyses such as ex-situ XPS, XRD and HR-TEM. Detailed investigations on structural and electrochemical cycling stability of MnCr2O4/G (MCO/G) composite anodes recommend the title electrode as a potential next generation anode material for high capacity LIBs with scalability possibilities through cost effective approach. [Display omitted]