Effect of ball-milling solvent on the structure and lithium storage performance of Fe₂SiO₄/C nanocomposite

Abstract

Ethanol, deionised water and their mixture were used as the ball-milling solvents to prepare Fe2SiO4/C nanocomposites via solid-state reactions from ferrous oxalate, nano silica and ammonium citrate. The three Fe2SiO4/C nanocomposites are orderly designated as FS/C-E, FS/C-W and FS/C-M and exhibit different structure. XRD results indicate that all three Fe2SiO4/C nanocomposites are fayalite crystal phase and FS/C-M has developed (111) lattice planes. SEM results further indicate that FS/C-M has the smallest particle size among the three Fe2SiO4/C nanocomposites. TEM also results indicate that Fe2SiO4 nanoparticles are evenly dispersed the carbon networks of FS/C-M. These unique structure ensure FS/C-M deliver a high charge capacity of 718.3 mAh/g at 0.1 C, high rate performance (391.6 mAh/g at 5 C) and good cycling performance (707.4 mAh/g at 1 C after 200 cycles).