Preparation and Electrochemical Performance of ZnO Films as Anode Materials for Li-Ion Batteries

In this work, the effect of rf power on the structural, electrical and electrochemical properties of ZnO thin films was investigated. ZnO thin films were deposited on glass and Cr coated stainless steel substrates by rf magnetron sputtering in pure Ar gas environment. ZnO thin films for different rf powers (75, 100, and 125 W) were deposited keeping all other deposition parameters fixed. ZnO thin films were used as negative electrode materials for lithium-ion batteries, whose charge-discharge properties, cyclic voltammetry and cycle performance were examined. A high initial discharge capacity about 908 mAh g^{-1} was observed at a 0.5 C rate between 0.05 and 2.5 V. The crystallographic structure of the sample was determined by X-ray diffraction. The electrical resistivity of the deposited films was measured by the four-point-probe method. The thickness of the ZnO thin films was measured using a profilometer.