Bismuth-Based Multimetal Oxides: Evaluation of Their Photoelectrochemical and Photocatalytic Properties

One of the approaches used to improve the photocatalytic activity of single metal oxides is to use a foreign atom as a dopant to facilitate improved light absorbance/charge separation. Unlike, single metal oxides, using multimetal oxides offer the option to include an additional element as a defacto part of the structure to aid in tuning the band edge positions, improving light absorbance, and enhancing photocatalysis.

Of particular interest is the use of bismuth which allows the shifting of the valence band closer to the conduction band to reduce bandgap. In this presentation, bismuth titanates will be examined as a case study on multimetal oxides. BTO will be evaluated for its photocatalytic and photoelectrochemical properties. The role of 3d elements in altering the photocatalytic properties of the BTO is presented. Photoelectrochemical techniques can aid in the fundamental understanding of the charge generation, separation, and transport in such oxides. To this end, the electrochemical responses of the bismuth titanate films and the effects of a third element inclusion will be discussed.

The insights drawn from this work can aid in designing new formulations that represent other oxide family groups such as scheelites, delafossites, or perovskites.