Fabrication of Mesoporous Graphene@Ag@TiO2 Composite Nanofibers Via Electrospinning as Anode Materials for High-Performance Li-Ion Batteries

Abstract

Nanosized TiO2 has been actively developed as a low-cost and environment-friendly anode material for lithium-ion batteries (LIBs), but its poor electronic conductivity seriously restricts its practical applications. This drawback is addressed in this work by the fabrication of one-dimensional mesoporous graphene@Ag@TiO2 composite nanofibers as anode materials for high-performance LIBs. The materials were prepared via electrospinning combined with annealing treatment, and the effects of graphene addition on the microstructure and electrochemical performance of the resulting mesoporous graphene@Ag@TiO2 nanofibers were investigated in detail. Ag@TiO2 nanofibers with the optimal amount of graphene displayed a maximum initial discharge capacity of [Formula: see text] at [Formula: see text] and retained a discharge capacity of [Formula: see text] at [Formula: see text] after 100 cycles. These results reflect the excellent cycling stability of the material. The average specific discharge capacity of the nanofibers ([Formula: see text] at [Formula: see text] was two-fold higher than that of samples without graphene, and their discharge capacity returned to [Formula: see text] (approximately [Formula: see text] for other nanofibers) when the current density was recovered to the initial value ([Formula: see text]. Electrochemical impedance spectroscopic measurements confirmed that the conductivity of the electrode was [Formula: see text], which is higher than that of bare mesoporous Ag@TiO2 ([Formula: see text]). Thus, one-dimensional mesoporous graphene@Ag@TiO2 nanofibers can be regarded as a promising anode material for LIBs.