Solar Thermal Decoupled Process: The Rotating Disc Electrode's Effect on Mass Transfer of Cobalt Oxide
Jon Schoer; Luke Venstrom
Mechanical Engineering and Chemistry
In order to make the production of H2 (a fuel) from H2O in a decoupled solar thermal-electrolysis process commercially viable, current densities of at least 50 mA/cm2 during electrolysis are required. When the cobalt oxide electrolyte is quiescent in our electrolysis cell, current densities are far below this value. One approach to increasing the current density is to mechanically increase fluid motion (convection) to enhance mass transfer to the electrode surface. To assess the impact of convection on mass transfer and to better understand the kinetics involved in the process, we employed a rotating disc electrode. Our results show that the current density increases, as expected from the Levitch equation. However, it has proven challenging to quantify the increase and to model the kinetics due to difficulties in repeatability of the experiment. In this poster we describe our current findings with convective mass transfer and relate them to our previously developed model for the electrochemical kinetics under quiescent conditions. Extending our model to convective mass transfer will allow the model to be more effectively used to develop and evaluate commercial cell designs that could be implemented for the efficient production of H2 from H2O, a sustainable solar fuel.
Silcox, Rachel and Villagran, Guadalupe, "Solar Thermal Decoupled Process: The Rotating Disc Electrode's Effect on Mass Transfer of Cobalt Oxide" (2018). Symposium on Undergraduate Research and Creative Expression (SOURCE). 707.