Co–MnO/C nanoparticles derived from MOFs with improved conductivity and reduced volume change for lithium-ion batteries

Abstract

MnO, used as an anode material for lithium-ion batteries (LIBs), suffers from severe volume changes, poor conductivity and limited cycle performance. Herein, we applied carbon materials derived from metal–organic frameworks (MOFs) to obtain a considerable specific surface area and fitting aperture, which can be used to physically fix MnO nanoparticles. The ultrafine Co particles further anchor MnO nanoparticles through chemical interaction. The combination of physical and chemical anchoring of MnO alleviated the problem of volume changes during the intercalation reaction of LIBs. The composite of carbon material and the doping of transition metal Co improved the conductivity of MnO. In addition, the convenient channel provided by the porous structure for the diffusion of ions, the slowing down of volume changes during the process of lithiation/delithiation and the improvement in conductivity are propitious to electrochemical performance of LIBs. Therefore, Co–MnO/C delivered an ultrahigh capacity of 1653 mA h g⁻¹ at 100 mA g⁻¹. The specific capacity tested at 100 and 1000 mA g⁻¹ can still reach 1414 and 772 mA h g⁻¹, respectively, after about 300 cycles. Mn-based materials with their outstanding electrochemical performance, environmental friendliness and convenient synthesis strategy demonstrate the feasibility of Co–MnO/C composite materials in practical applications of LIBs.