CTAB-assisted synthesis of ZnCo2O4 nanoparticles embedded in N-doped carbon as superior anode materials for lithium-ion battery

Abstract

One of the most effective methods to reduce the volume expansion of metal oxides is by designing nanosized metal oxides and forming composites with carbon materials. In this work, we report a simple method for constructing quasi-spherical ZnCo2O4 nanoparticles using a cetyltrimethylammonium bromide (CTAB) assisted sol-gel autocombustion method, followed by coating with an N-doped carbon layer to form a core-shell structure. When evaluated as anode material for Lithium ion battery, the novel core-shell structure electrode delivers a high capacity of 1146.6 mAh g−1 at a current density of 500 mA g−1 after 100 cycles. The electrode also demonstrates a high cycle stability with a good capacity of 811.3 mAh g−1 for 200 cycles at a current density of 2 A g−1. This performance is due to the carbon coating layer, which improves the electrical conductivity, relieves the volume expansion and mitigates the agglomeration of the ZnCo2O4 nanoparticles. Furthermore, the coating also ensures that a stable SEI layer forms at the outer surface of the robust carbon.