Co/CoO particle within F, N-codoped mesoporous carbon framework for anode of lithium-ion batteries

Abstract

Lithium-ion batteries (LIBs) have attracted immense attention as a main power supplier for electronic devices because they have a high energy density and long cycle life. Graphite has mainly been used for the anode material of LIBs, because it is chemically stable, has a high electrical conductivity, and is inexpensive. However, the low theoretical specific capacity of graphite limits the application of LIBs. One prospective strategy for achieving high-performance anodes is a hybrid composite structure, which utilizes various materials. Herein, a novel composite structure of a Co/CoO particle within an F, N-codoped mesoporous carbon framework was synthesized using a biomass impregnation process followed by a carbonization step. During the impregnation process, the biomass absorbed Co(NO3)2·6H2O and the NH4F precursor, which facilitated the formation of Co(OH)2 and CoO. During the carbonization, CoO particles were partially reduced to Co/CoO, and embedded into the F, N-codoped mesoporous carbon framework. The resulting Co/CoO/C 4M anode exhibited superior anode performances, including a high specific capacity of 557.37 mA h/g after 100 cycles at a current density of 100 mA/g and an excellent fast lithium-ion storage capability of 403.17 mA h/g after 1000 cycles at 2000 mA/g. The Co/CoO/C 4M anode can provide a reasonable reference point for hybrid composited anode materials for use in accomplishing high-performance and long-cyclable LIBs.