Preparation and characterization of a PbTiO₃ + PbO mixed-oxide photoelectrode

Abstract

A new PbTiO₃ + PbO photoelectrode system for a photoelectrochemical cell has been prepared from a mixture of β-PbO₂ and TiO₂ by solid state sintering. The crystal structure and surface morphology of the mixture were determined by X-ray diffraction and scanning electron microscopy respectively, and energy dispersive X-ray analysis measurements were used to establish the phases present. These studies reveal the photoelectrode as a PbO-rich PbTiO₃ mixed-phase oxide with high tetragonality and a crystalline nature. Mott-Schottky plots and photoelectrochemical measurements, such as the action spectrum, I-V characteristics etc., of this mixed oxide were evaluated in 0.1 M Fe(CN)^3-/4-₆ (pH 9.2 buffer) redox electrolyte. These investigations suggest that the mixed-oxide electrode exhibits n-type conductivity, a decreased band-gap energy and an enhanced absorption range in the visible region.