Facile synthesis of free-standing Fe2O3/carbon nanotube composite films as high-performance anodes for lithium-ion batteries

Abstract

Continuous Fe nanoparticles (NPs)/carbon nanotube (CNTs) composite films have been fabricated with the CVD gas flow reaction using ferrocene as a catalyst and ethanol as a carbon precursor. The as-spun Fe NPs/CNTs films are converted to Fe₂O₃ NPs/CNTs films by an annealing process in air at a temperature of 500 °C. The as-prepared Fe₂O₃ NPs/CNTs films are still highly flexible. Scanning electron microscopy (SEM) and transmission electron microscopy observations reveal the Fe₂O₃ NPs are homogeneously bonded with the CNT network. In addition, the flexible and conductive 3D CNTs networks endow the as-synthesized composite with increased electrical conductivity and mechanical stability. As a result, the as-synthesized flexible and transferrable composite films deliver an initial reversible capacity of 985.8 mA h g⁻¹ at a current density of 30 mA g⁻¹, and maintain a high reversible capacity of 392.4 mA h g⁻¹ even at a current density up to 3 A g⁻¹. Meanwhile, Fe₂O₃ NPs/CNTs films exhibit an excellent cycling performance with a reversible capacity of 375.5 mA h g⁻¹ after 800 cycles at a current density of 3 A g⁻¹.