Work

Effect of Annealing on LiCoO2 Thin Film Deposited by RF Magnetron Sputtering

Year: 2025

Type: article

Abstract: This study investigates the properties of LiCoO2 coatings as cathodes for lithium-ion batteries, focusing on the effects of annealing on their structural, morphological, chemical, vibrational, and electrochemical characteristics. The LiCoO2 coatings were deposited on silicon and glass substrates using RF magnetron sputtering at 100 W and subsequently annealed at 600 °C for 1 h. The films were characterized before and after annealing using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and electrochemical impedance spectroscopy (EIS). Annealing improved the crystallinity of LiCoO2, which is critical for enhancing lithium-ion diffusion. Furthermore, an XPS analysis revealed a layered structure with a Li-rich outer layer and a Co-rich underlayer, indicating a more uniform distribution of Li and Co, along with increased oxygen content. Additionally, the annealing process refined the microstructure of the LiCoO2 coating, positively impacting its electrochemical performance. A comparative analysis of cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) results demonstrated a significant improvement in the charge/discharge capacity post-annealing. This study successfully highlights the beneficial effects of annealing on LiCoO2 thin-film cathodes, offering valuable insights for developing more efficient and sustainable lithium-ion batteries through sputter-deposition processes.

Source: Materials

DOI: 10.3390/ma18061217