Cobalt-doped Titanium Dioxide Photochemical Fuel Cell for Wastewater Purification

In this work, a photovoltaic electrochemical fuel cell consisting of a cobalt-titanate (CoTiO3) anode and a platinum (Pt) cathode was utilized for the decomposition of environmentally hazardous materials in wastewater. The CoTiO3 nanotubes (NTs) were prepared through electrochemical oxidation of pure titanium (Ti) strips. The titanium dioxide (TiO2) nanotubes were doped with a cobalt salt via electrospinning followed by annealing to form CoTiO3. The addition of cobalt to the TiO2 NTs was tested to observe if photochemical catalytic properties increased in the presence of ultraviolet and visible light. The increases in photochemical catalytic properties were validated by comparing the measured electric potential differences (∆E) between the CoTiO3 test samples, and the TiO2 control samples. It is concluded that the cobalt doped anode greatly increases the response of the fuel cell system to visible light stimulus. This allows for greater utility generation capacity and faster photochemical catalytic reaction at the anode surface. The application of cobalt doped titanium dioxide anodes in photovoltaic electrochemical fuel cells increases the photoelectric energy conversion efficiency and waste decomposition rate. There is potential to scale the system up for practical applications.