A comprehensive evaluation of Co, Ni, Cu and Zn doped manganese oxalate for lithium storage

Abstract

Transition metal oxalates have attracted people's attention owing to their low cost, low lithium insertion potential and high theoretical reversible capacities. Disappointingly, high irreversible capacity thanks to the formation of SEI as well as the consumption and exfoliation of active materials during the process of cycling severely restrict its application of it. In this work, a comprehensive evaluation of Co, Ni, Cu and Zn doped manganese oxalate was made. All samples are synthesized via facile and time-saving microwave hydrothermal method. It is intriguing that merely 30 ​min is required to accomplish the entire process and all samples possess fine electrochemical performance. As far as the four bimetallic oxalates, the resulting Mn0·5Ni0·5C2O4 exhibits the optimum performance (746.2 ​mA ​h ​g−1 after 100 cycles at 0.2 ​A ​g−1 and 546.7 ​mA ​h ​g−1 at 1 ​A ​g−1 after 400 cycles), which can be attributed to one-dimensional rod-like morphology of Mn0·5Ni0·5C2O4 as well as the synergistic and catalytic effect of Mn and Ni, resulting in faster electrode kinetics. Mn0.5Ni0.5C2O4 displays incalculable potential and can be applied in the highly reversible lithium-ion batteries.