Sol-gel synthesis of nano block-like ZnMn2O4 using citric acid complexing agent and electrochemical performance as anode for lithium-ion batteries

Spinel ZnMn2O4 anode material has high research value as a potential alternative anode material for lithium-ion batteries due to the limited theoretical capacity of commercial graphite. This study prepared a block structured lithium-ion battery anode material ZnMn2O4 using the citric acid sol-gel combustion method. The thermal decomposition process of the xerogel precursors was investigated using thermogravimetric differential thermal analysis. When the ratio of citric acid to metal cations is 4:1, the prepared ZnMn2O4 material had an uneven block structure (ca. 0.3–1.3 µm). The material shows high electrochemical performance: the initial capacity is as high as 1100.2 mAh·g−1 at 0.1 C, and the capacity remains at 277.6 mAh·g−1 after 40 cycles. Finally, the first discharge and the second charge–discharge processes of ZnMn2O4 were thoroughly investigated, and the electrochemical behavior in the electrochemical process was analyzed.