Abstract:
Silicon dioxide (SiO
2) is considered a promising anode material for lithium-ion batteries due to its high theoretical specific discharge capacity (1 965 mAh/g) and extremely low cost. However, its high oxygen content leads to poor electrochemical activity. To address this issue, a mesoporous SiO
2 with a particle size of approximately 100 nm was designed and prepared via the sol-gel method, using tetraethyl orthosilicate (TEOS) as the precursor and cetyltrimethylammonium bromide (CTAB) as the template. The prepared SiO
2 particles were subsequently coated using resorcinol formaldehyde resin (RF) as the carbon precursor. Based on the above experiments, Cu
2+ and Fe
3+ were doped into the resin layer through a complexation reaction. After high-temperature carbonization, a bimetal-loaded carbon-coated material, SiO
2@Cu-Fe-C, was formed. The synergistic effect generated by the bimetallic loading effectively improved the electrochemical performance of the material. The data showed that the initial Coulombic efficiency (ICE) of SiO
2@Cu-Fe-C was 52.2%. It exhibited a high reversible specific discharge capacity of 719 mAh/g at a current density of 200 mA/g, and maintained an average specific discharge capacity of 570 mAh/g at a current density of 1 000 mA/g after 500 cycles.