Raspberry-Shaped Nickel-Enhanced MnO-Based Carbon-Containing Nanostructures as Anode Materials for Li-Ion Batteries

Transition metals and their oxides have been extensively studied as anode materials for lithium-ion batteries (LIBs) due to their high theoretical capacities. The porous structure of electrode materials not only supplies some empty spaces to resolve the volume change but also provides many charge transfer channels. Herein, we have synthesized a porous raspberry-like nickel-enhanced MnO-based carbon-containing composite (Ni/MnO-C) by one hydrothermal step and subsequent calcination. Upon adding metallic nickel, the overall conductivity of MnO is successfully improved, which increases the specific capacity of LIBs. The porous nanostructure composed of many uniform nanoparticles with enough buffer space can effectively prevent the structural damage caused by volume variation. When raspberry-like nanostructures are broken into some small nanoparticles, more active sites are exposed and some additional capacities are provided. Employed as anode materials for LIBs, the Ni/MnO-C electrodes have a high first discharge specific capacity of 1536.9 mAh g–1 at 0.2 A g–1. Impressively, the reversible capacity of Ni/MnO-C can be retained after 3500 long-term cycles at a current density of 1 A g–1. Additionally, the practical applications of Ni/MnO-C in LIBs are demonstrated through some usual electronic equipment, which will inspire the evolution of energy storage devices.