A Hierarchical, Nanofibrous, Tin-Oxide/Silicon Composite Derived from Cellulose as a High-Performance Anode Material for Lithium-Ion Batteries

A hierarchical nanofibrous tin-oxide/silicon composite with tin oxide nanoparticles anchored on the silicon nanofiber surface is fabricated employing natural cellulose substance (ordinary filter paper) as structural template. Tin oxide gel is deposited uniformly onto the surface of the silicon nanofibers that prepared by magnesiothermic reduction of the silica replica of the filter paper, and thereafter, the as-prepared tin-oxide-gel/silicon nanocomposite is calcined in argon atmosphere to yield the tin-oxide/silicon nanocomposite. The resulted tin-oxide/silicon nanocomposite possesses a hierarchical network structure that inherited from the initial cellulose substance. When the nanocomposite is evaluated as an anode material in lithium-ion batteries, it exhibits superior lithium storage properties compared with the pure silicon nanofiber and tin oxide powder matters. For such a nanocomposite with 58.8 wt% tin oxide content delivers a specific reversible capacity of 547.8 mAhg(-1) after 150 discharge/charge cycles at 100 mA g(-1). The improved lithium storage performances are attributed to the unique three-dimensional hierarchical porous network structure of the nanocomposite, high dispersed fine tin oxide nanoparticles on the silicon nanofiber surface, as well as the synergistic effects between the silicon nanofibers and the tin oxide nanoparticles on the lithium storage.