Long-term durable silicon photocathode protected by a thin Al2O3/SiOx layer for photoelectrochemical hydrogen evolution

The long-term steady production of H2 is vital for p-Si photocathodes. However, the oxidation of a Si photoelectrode substantially deteriorates its performance, over time. This study demonstrates that a thin Al2O3 layer deposited over the Si can prevent oxidation and also reduce overpotential, via a surface passivation effect.