Multilayer iron oxalate with a mesoporous nanostructure as a high-performance anode material for lithium-ion batteries

In the search to improve the irreversible capacity of transition-metal oxalates, iron oxalate with a multilayer and mesoporous nanostructure has been produced via a liquid-phase precipitation method with the use of a solvent. The feeding sequence and self-assembly, considering hydrophobic interlamination interactions and the interconnection between ethanol molecules and the crystallographic planes, have been investigated to determine their influence on the customized structure and morphology. The unique structural organization significantly improves the electrochemical properties to achieve a high discharge capacity of ∼1521.2 mAh g−1 at 1 C current rate, exhibiting a capacity retention of 63.29% for the first cycle and delivering approximately 65.30% in the 200th cycle; a satisfactory cycle and rate performance of ∼993.3, ∼723.1, ∼710.7, and ∼584.3 mAh g−1 for 1, 3, 5 and 10 C after 200 cycles, respectively; and slight voltage hysteresis. The high capacity is a result of the mesoporous nanostructure, which provides additional volume availability and enhances the capacitive effect. The favourable capacity retention, reasonable rate performance, and cycling stability are attributed to the multilayer structure with additional unobstructed and stable channels for Li+ and electron diffusion.