Synthesis of ultrafine Co3O4 nanoparticles encapsulated in nitrogen-doped porous carbon matrix as anodes for stable and long-life lithium ion battery

Abstract

Hybrid nanostructures with ultrafine metal oxides in porous nitrogen-doped carbon matrix have received great attention for the enhancing performance of lithium-ion batteries because of their advantages in effectively solving the problems during the discharge/charge processes, such as low conductivity, large volume expansion, and long diffusion path for the fast transfer of Li+ ion. Herein, we report a facile strategy for the synthesis of ultrafine Co3O4 nanoparticles uniformly encapsulated into nitrogen-doped porous carbon matrix (Co3O4@NC) through pyrolysis of metal-organic frameworks (MOFs) followed by a hydrothermal oxidation method. Moreover, Co3O4@NC inherited the advantage of MOFs with porous structure, and the as-synthesized Co3O4 nanoparticles uniformly distributed into the simultaneously generated nitrogen-doped carbon matrix. Benefiting from its unique structural features, Co3O4@NC exhibits a large discharge capacity of 1017 mAh g−1 after 100 cycles at 100 mA g−1, and the long reversible capacity of 731 mAh g−1 can be retained after 1000 cycles at 1000 mA g−1, indicating that Co3O4@NC has potential application in lithium-ion batteries with long cycling life and high power density.