Physical vapor deposition of Sb2Se3 films as high-performance anode materials in quasi-solid-state Li-ion batteries

Antimony selenide (Sb2Se3) thin films with cluster morphology were prepared using physical vapor deposition method combined with the post-annealing process. The composition and morphology of the prepared films were characterized by X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. Electrochemical analysis of the samples revealed that the Li/Sb2Se3 half-cell exhibited an initial discharge specific capacity of 825.7 mAh∙g−1 at a current density of 0.5 C, and a discharge specific capacity of 1192.7 mAh∙g−1 after 100 charge-discharge cycles. The Sb2Se3 film also displayed excellent rate characteristics and a high cycling performance with a high discharge specific capacity of 812.2 mAh∙g−1 at current density of 2 C after 600 charge-discharge cycles. Results obtained from the galvanostatic intermittent titration tests and from electrochemical impedance spectroscopy proved that the cluster structure of the thin film was beneficial to the ion transport characteristics, as well as for the rate performance of the Sb2Se3 thin film materials. A quasi-solid-state battery based on Sb2Se3/Li1.3Al0.3Ti1.7(PO4)3/LiFePO4 was also assembled, which provided a discharge specific capacity of 445.5 mAh∙g−1 at 0.5 C with a capacity retention rate of 49.7% after 200 charge-discharge cycles. The results of this study clearly suggest that the use of Sb2Se3 films as anode materials can provide promising results in the performance enhancement of quasi-solid-state Li-ion batteries.