Al nanorod thin films as anode electrode for Li ion rechargeable batteries

Abstract

Nanocolumnar aluminum thin films (Al nanorod films) were grown on Titanium (Ti)/glass substrates in a vacuum at different oblique inclination angles by an electron-beam evaporator. The Al nanorod/Ti/glass substrates were used as anode electrode for lithium (Li) ion batteries. The thickness of the Al nanorod thin films was controlled to be 100 nm, which was confirmed by their cross-section microstructure. The X-ray diffraction (XRD) patterns showed a highly textured (I 1 1) orientation for all the films, regardless of the deposition angle, revealing that the as-synthesized products are made of high purity Al. X-ray photoelectron spectroscopy (XPS) analysis confirmed that the peak of the Al film was observed at a binding energy of 74.24 eV. A three-electrode cell was employed for the Li ion battery performance tests, in which metallic Li sheets were used as counter and reference electrodes. The galvanic charge-discharge profiles were carried out at a constant current of 700 mA g(-1) from 0.01 V to 3.00V. The aligned Al nanorod thin film demonstrated the highest specific capacity reported so far of 1293 mAh g(-1) in the propylene carbonate-dimethyl carbonate (PC-DMC) electrolytes, which is in close agreement with the theoretical one (1420 mAh g(-1)). The average columbic efficiency was observed to be 91%. (C) 2012 Elsevier Ltd. All rights reserved.