Figure 4.
XPS spectra of Cu 2p core level spectra from a) CuO photocathode, b) CuO:G‐NH2 photocathode, and c) CuO:G‐COOH photocathode.
XPS spectra of Cu 2p core level spectra from a) CuO photocathode, b) CuO:G‐NH2 photocathode, and c) CuO:G‐COOH photocathode.