PHOTOELECTRICALCHEMICAL PERFORMANCE OF TUNGSTEN DOPED BIVO4 FILMS

Due to advances in fuel cell technologies, hydrogen gas has emerged as a promising alternative fuel source. Currently, most hydrogen is produced by methods that require methane gas as an input and release significant pollutant and greenhouse gases. However, hydrogen gas can be sustainably produced from water and sunlight through a process known as photoelectrolysis. Materials suitable for the production of hydrogen gas through photoelectrolysis have been the subject of research for over 40 years. Recently, bismuth vanadate, BiVO4, has shown promise as a photosensitive electrode material for photoelectrochemical (PEC) water splitting. In this study, thin-films of BiVO4 produced by ultrasonic spray pyrolysis of aqueous solutions containing bismuth nitrate and vanadium oxysulfate were produced. N-type doping of the samples was achieved by introducing tungsten containing compounds to the precursor solutions. The PEC performances of these materials were tested under simulated solar light conditions and the photocurrent densities generated by the materials were measured and compared. Results indicated that doping BiVO4 by introducing silicotungstic acid in the precursor solution improved the PEC performance of the material when mixed in the appropriate ratios. However, the undoped samples produced larger photocurrent densities. It is hypothesized that the silicon from the silicotungstic acid is interfering with the conductivity of the material. Therefore other tungsten precursor solutions are being investigated, such as ammonium metatungstate, (NH4)6H2W12O40 xH2O. The results of this ongoing research will be presented.

Additional Abstract Information

Student(s): Melissa R. Dutter

Department: Engineering

Faculty Advisor: Dr. Stephen Keith Holland

Type: Oral

Year: 2013