Anchoring Fe3O4 nanoparticles on three-dimensional carbon nanofibers toward flexible high-performance anodes for lithium-ion batteries

There is growing interest in flexible, cost-effective, and binder-free energy storage devices to meet the special needs of modern electronic systems. Herein we report a general, scalable, eco-friendly, and cost-effective approach for the fabrication of nano-Fe3O4-anchored three-dimensional (3D) carbon nanofiber (CNFs) aerogels (Fe3O4@BC-CNFs). The preparation processes include the anchoring of Fe2O3 nanoparticles on bacterial cellulose (BC) nanofibers with intrinsic 3D network structure and subsequent carbonization at different temperatures. The aerogel carbonized at 600 degrees C (Fe3O4@BC-CNFs-600) is highly flexible and was directly used as working electrodes in lithium-ion batteries without metal current collectors, conducting additives, or binders. The Fe3O4@BC-CNFs-600 demonstrates greatly improved electrochemical performance in comparison to the bare Fe3O4 nanoparticles. In addition to its excellent flexibility, a stable capacity of 755 mAh g(-1) for up to 80 cycles is also higher than most of carbon-Fe3O4 hybrids. The high reversible capacity and excellent rate capability are attributed to its 3D porous network structure with well-dispersed Fe3O4 nanoparticles on the surfaces of CNFs. (C) 2015 Elsevier B.V. All rights reserved.