Porous NiO/graphene composite thin films as high performance anodes for lithium-ion batteries

Abstract

Porous NiO and NiO/graphene (NiOG) thin film electrodes were prepared by electrostatic spray deposition (ESD) technique and investigated as anodes for lithium ion batteries. The porous NiO structure was designed to better buffer the mechanical stress induced by the volume change of NiO as well as inhibit the aggregation of nanoparticles during conversion reaction. Aiming to facilitate better reaction kinetics compared to pure NiO electrode, graphene nanoplates were added to form NiOG composite film where additional graphene could be helpful for the electron transfer as conductive medium. As a result, porous NiOG composite thin film electrode exhibits high rate capability (759, 774, 614, 447, 243 and 104mAhg−1 at 0.1, 0.2, 0.5, 1, 2, and 5Ag−1, respectively) and excellent cycling performance (no capacity decrease for 500 cycles at 0.5Ag−1). From analyzing cyclic voltammetry (CV) curves, rate and cyclical performance, and electrochemical impedance spectroscopy (EIS), it was concluded that NiOG composite electrodes exhibited enhanced electrochemical performance compared to NiO electrodes.