Development of Non-Pt Electrocatalysts towards Hydrogen Evolution Reaction for Gas-phase Br-2-H-2 Flow Battery

A gas-phase HBr/Br-2 flow battery is setup. The equilibrium cell potential of the flow battery is calculated by Nernst equation incorporated with Br-2-HBr-H2O phase equilibrium in Aspen OLI lab. The calculated equilibrium cell potential is compared with the experimental open circuit voltage. Polarization of this flow battery is investigated at both electrolzyer and fuel cell modes with respect to different content of bromine. Because of the poisoning effect of bromine and bromide ions on Pt, non Pt electrode materials need to be developed. For the hydrogen evolution reaction (HER), activities of MoS2 and IrO2/C are tested on the rotating disk electrode with cyclic voltammetry and psedosteady state polarization. XRD and HRTEM are used to characterize the morphology and structure.