Structural and Electrochemical Properties of Binary ZnO:Al Nanocomposites as Anode for Lithium-ion Batteries

Abstract

In conventional lithium-ion batteries (LIBs), carbon compounds are commonly utilised as the anode owing to their great performance, low cost, and abundance. However, due to the limited storage capability of pure carbon materials that restrict further improvement of LIBs, zinc oxide (ZnO) has been one of the promising anode materials to be used as an alternative to strengthen the electrochemical performance of LIBs due to its high theoretical capacity of 987 mAh g-1. This study aims to synthesise ZnO:Al nanowires using the hot-tube thermal evaporation method. Three types of samples are made using this method by varying the concentration of 0 wt% (S1), 3wt% (S2), and 6 wt% (S3) of aluminium (Al) during the Al deposition process. The EDX findings indicated that the sample has a high proportion of zinc (Zn) and oxygen (O), with the S3 sample having the highest Al concentration after being deposited. The most substantial diffraction peak for XRD of all samples was found at (101), exhibiting a single crystalline hexagonal structure with optimum growth direction on the c-axis. For EIS analysis, the S3 sample has the lowest bulk resistance and maximum ionic conductivity. In conclusion, the ZnO sample with 3 wt% of Al as a dopant was selected as the optimum result to synthesise a homogenous surface of ZnO:Al with good crystallinity by using a hot-tube thermal evaporation process and giving the best conductivity in electrochemical performance.