Stabilizing CuO photocathode with a Cu3N protection shell

CuO, as a promising photocathode material, suffers from severe photocorrosion in photoelectrochemical water splitting applications. Herein, Cu3N protection shell was used to protect the CuO for first time effectively suppress of CuO. Consequently, Cu3N-protected shows improved stability, retaining 80% its initial current density 20-min test, while only 10% can be retained bare photocathode. This work may provide an important strategy using shells stabilize unstable photocathodes.