Fabrication of (Co,Mn) ₃O ₄/rGO Composite for Lithium Ion Battery Anode by a One-Step Hydrothermal Process with H ₂O ₂ as Additive

Abstract

Binary transition metal oxides have been regarded as one of the most promising candidates for high-performance electrodes in energy storage devices, since they can offer high electrochemical activity and high capacity. Rational designing nanosized metal oxide/carbon composite architectures has been proven to be an effective way to improve the electrochemical performance. In this work, the (Co,Mn) ₃O ₄ spinel was synthesized and anchored on reduced graphene oxide (rGO) nanosheets using a facile and single hydrothermal step with H ₂O ₂ as additive, no further additional calcination required. Analysis showed that this method gives a mixed spinel, i.e. (Co,Mn) ₃O ₄, having 2 ⁺ and 3 ⁺ Co and Mn ions in both the octahedral and tetrahedral sites of the spinel structure, with a nanocubic morphology roughly 20 nm in size. The nanocubes are bound onto the rGO nanosheet uniformly in a single hydrothermal process, then the as-prepared (Co,Mn) ₃O ₄/rGO composite was characterized as the anode materials for Li-ion battery (LIB). It can deliver 1130.6 mAh g ^-1 at current density of 100 mA g ^-1 with 98% of coulombic efficiency after 140 cycles. At 1000 mA g ^-1, the capacity can still maintain 750 mAh g ^-1, demonstrating excellent rate capabilities. Therefore, the one-step process is a facile and promising method to fabricate metal oxide/rGO composite materials for energy storage applications.