Semiconductor Photocatalysis and H2 Gas Evolution With Ag-TiO2 Nanocrystals — 83a — Lara Haack, Nurul Muttakin, Mahfuz Ahammed Swadhen, Paschal Akubuiro, Dagyn Williams

Energy usage around the world is expected to increase by almost 20 million kWh by 2050. One way we can close this gap is by utilizing solar energy, which is present in abundance here on Earth. By synthesizing titanium dioxide nanocrystals, we could make usable fuel in the form of hydrogen gas through water splitting and semiconductor photocatalysis. We were able to characterize our products with UV-vis spectroscopy and X-ray diffraction. To account for the limited light absorption of titanium dioxide, we doped the material with cobalt to increase its absorption into the visible region. We initially loaded the surface of the TiO₂ nanocrystals with cobalt, followed by thermally driven ion diffusion into the TiO₂ host. By using this method we have control over the concentration of cobalt in the nanocrystal. We also prepared Ag-TiO₂ hetero nanocrystals with doped and non-doped TiO₂. The silver–titanium dioxide heterojunctions allow separation of photogenerated charge carriers to promote photocatalysis. Both methods could yield better results towards hydrogen gas production as a stable energy source.

University of South Dakota
Dr. James Hoefelmeyer