Composite p-Si/AlO/Ni Photoelectrode for Hydrogen Evolution Reaction.

A photoelectrode for hydrogen evolution reaction (HER) is proposed, which is based on p-type silicon (p-Si) passivated with an ultrathin (10 nm) alumina (AlO) layer and modified with microformations of a nickel catalyst. The AlO layer was formed using atomic layer deposition (ALD), while the nickel was deposited photoelectrochemically. The alumina film improved the electronic properties of the substrate and, at the same time, protected the surface from corrosion and enabled the deposition of nickel microformations.

Silicon Passivation by Ultrathin Hafnium Oxide Layer for Photoelectrochemical Applications.

Hafnium oxide (HfO) films on silicon have the potential for application in photovoltaic devices. However, very little is known about the photoelectrochemical and protective properties of HfO films on Si. In this study, ultrathin films of HfO in the range of 15-70 nm were deposited on p-Si and Au substrates by atomic layer deposition (ALD).

Photoelectrolysis of water: Solar hydrogen--achievements and perspectives.

Thermodynamic analysis of energy conversion from light-to-chemical, light-to-electric and electric-to-chemical is presented by the case study of water photoelectrolysis on TiO(2) surface. It is demonstrated that at the current state-of-the-art energy conversion efficiency of water photoelectrolysis can be increased approximately 17 times by separating the processes of solar-to-electric and electric-to-chemical energy conversion and optimizing them independently. This allows to mitigate a high overvoltage of oxygen evolution reaction with respect to thermodynamic E(0)(O(2)/H(2)O) = 1.