| Abstract Scope |
Electrides, with exceptional electron-donating capabilities, are promising materials for energy conversion, semiconductors, and environmental technologies. This study introduces a novel method to form a stable surface electron layer on copper (Cu) by physically contacting Gd₂C electride and Cu metal. Unlike cathodic protection, this approach directly injects excess electrons into pre-formed Cu surfaces by utilizing the work function difference between Gd₂C (2.8 eV) and Cu (4.6 eV), enabling non-oxidized Cu film. This process reduces the work function of the Cu film to 4.2 eV. Considering the surface state of the Gd₂C electride, we find the cleaved Gd₂C surface shows a significant electron transfer ability compared to the polished surface. The transferred excess electrons in Cu can be accumulated at the surface due to the Gauss’ law, giving an invisible electron layer. Finally, we suggest that the surface electron layer prevents Cu oxidation, paving the way for sustainable, energy-efficient semiconductor technologies. |