A theoretical approach to the design of reduced band gap noncorrosive electrodes for photoelectrochemical solar cells

Abstract

Preliminary results from our charge self-consistent LCAO band structure (CSCBS) calculations with Bloch sums as the basis reveal that a noncorrosive reduced band gap electrode for photoelectrochemical solar cells may be produced from a (1:1) mixture of β-PbO₂ and TiO₂ (both rutile). The band gaps for the constituents (β-PbO₂ and TiO₂) and the 1:1 mixture are calculated and a detailed characterization of the valence and the conduction bands is undertaken to offer a possible mechanism for the reduction of the band gap of the mixture. The band gap for the perovskite PbTiO₃ is also calculated to offer a guideline for selecting from the competing pathways to the fabrication of noncorrosive photoelectrochemical electrodes.