Synthesis of Mesoporous Fe 2 SiO 4 /C Nanocomposites and Evaluation of Their Performance as Materials for Lithium‐Ion Battery Anodes

The first kind of mesoporous Fe 2 SiO 4 /C nanocomposites (MFS‐1) were synthesized from the nano‐SiO 2 with a surface area of 137 m 2 ⋅g −1 and the second kind of mesoporous Fe 2 SiO 4 /C nanocomposites (MFS‐2) were prepared from the nano‐SiO 2 with a surface of 325 m 2 ⋅g −1 . XRD results indicate that α‐Fe 2 SiO 4 crystal phase appear in the two samples. SEM proves that the particle size of MFS‐2 (30‐40 nm) is smaller than that of MFS‐1 (40‐60 nm). TEM further proves Fe 2 SiO 4 nanoparticles are homogeneously dispersed in the carbon networking of MFS‐2. Pore structure analysis reveals that the specific surface area of MFS‐2 (136 m 2 ⋅g −1 ) is evidently larger than that of MFS‐1 (116 m 2 ⋅g −1 ), revealing the pore properties of mesoporous Fe 2 SiO 4 /C nanocomposites can be well controlled by using silica with different surface area. The above characters make MFS‐2 exhibit a high initial reversible capacity of 667 mAh⋅g −1 at 0.1 C, excellent rate capability (282 mAh⋅g −1 at 10 C) and improved cycling stability (606 mAh⋅g −1 at 1 C after 100 cycles).