1. (a) XRD pattern and optical image of the Li₂SiO₃ target; (b) XRD pattern and optical image of typical sample LiSiON- 100N9A1; (c) Cross-section and (d) top-view FESEM images of the typical sample LiSiON-100N9A1

2. (a) Survey-scan, (b) Si2p core-level, (c) O1s core-level, and (d) N1s core-level XPS spectra of Li₂SiO₃ target and typical sample LiSiON-100N9A1; (e) Schematic illustration of the partial structure change from Li₂SiO₃ to LiSiON with the incorporation of N

3. (a) Electrochemical impedance spectroscopy (EIS) spectra of the LiSiON thin films deposited under different conditions; (b) Schematic illustration of the Pt/LiSiON/Pt sandwich structure and the corresponding equivalent circuit; (c) CV curves of the LiSiON thin films deposited under different conditions; (d) Chronoamperometry curve of the sample LiSiON-100N9A1

4. (a) Cross-section FESEM image and corresponding EDS mapping images of the MoO₃/LiSiON/Li TFLB; (b) Typical CV curve, (c) initial three charge/discharge curves, (d) rate performance, (e) cycle performance, and (f) EIS spectra at different cycle numbers of the MoO₃/LiSiON/Li TFLB with sample LiSiON-100N9A1 as electrolyte