Hollow Porous VO/C Nanoscrolls as High-Performance Anodes for Lithium-Ion Batteries.

Novel hollow porous VO/C nanoscrolls are synthesized by an annealing process with the VO/octadecylamine (ODA) nanoscrolls as both vanadium and carbon sources. In the preparation, the VO/ODA nanoscrolls are first achieved by a two-phase solvothermal method using ammonium metavanadat as the precursor. Upon subsequent heating, the intercalated amines between the vanadate layers in the VO/ODA nanoscrolls decompose into gases, which escape from inside the nanoscrolls and leave sufficient pores in the walls. As the anodes of lithium-ion batteries (LIBs), such hollow porous VO/C nanoscrolls possess exceedingly high capacity and rate capability (904 mAh g at 1 A g) and long cyclic stability (872 mAh g after 210 cycles at 1 A g). The good performance is derived from the unique structural features of the hollow hierarchical porous nanoscrolls with low crystallinity, which could significantly suppress irreversible Li trapping as well as improve Li diffusion kinetics. This universal method of annealing amine-intercalated oxide could be widely applied to the fabrication of a variety of porous electrode materials for high-performance LIBs and supercapacitors.