Fe3O4 nanoparticle/high residual carbon nanofibril aerogels for anode material of lithium-ion battery with enhanced capacity

Transition metal oxide/carbon nanofibril composites are promising candidates for lithium-ion battery anode materials. However, when the transition metal oxide content is high, the network structure of the carbon nanofibrils is usually completely collapsed and serious agglomeration occurs. Moreover, when polymer (e.g. cellulose) is used as a carbon precursor, there is less carbon remained. Here, Fe3O4/carbon nanofibril aerogels with high residual carbon content were fabricated by doping with p-toluenesulfonic acid (TsOH) and crosslinking of surface-oxidized cellulose nanofibril with Fe3+. Consequently, the residual carbon of the composite doped with TsOH increased by 160% than the undoped sample. Furthermore, after 200 recharge and discharge cycles, the reversible capacity of the doped composite remained about 878 mAh g−1, which was 3.4 times higher than that of the undoped sample. Therefore, this work provides a facile pathway for construction of Fe3O4/carbon aerogels with high residual carbon and uniform nano-network structure for high-performance lithium-ion battery anode materials.