Rare earth rhodates of the distorted perovskite structure are semiconductors with a band gap of 2.2 eV. They may be doped either n- or p-type. The oxides are stable against photodecomposition at the potential for hydrogen evolution. With ceramic p-type LuRhO3 as the cathode and n-type TiO2 as the anode of an electrolytic cell sufficient photopotential is developed both to photoelectrolyze water in sunlight with no externally applied potential and to generate power simultaneously. LuRhO3 possesses deep lying impurity levels and surface capacitance does not exhibit ideal Mott-Schottky behavior. The Fermi level at the surface of LuRhO3 is pinned at the same potential independent of whether the oxide is p- or n-type.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Condensed Matter Physics
- Surfaces and Interfaces