Fig. 3

Comprehensive XPS scan of (a) Spin-coated CuS thin film; and (b) Doctor Blade-coated CuS thin film. Detailed S 2p spectrum for (c) Spin-coated CuS thin film; and (d) Doctor Blade-coated CuS thin film. High-resolution Cu 2p spectrum for (e) Spin-coated CuS thin film; and (f) Doctor Blade-coated CuS thin film.