The effect of organic additive on electrochemical fabrication of microstructured electrode for reverse electrodialysis

Abstract For reverse electrodialysis (RED) to be effectively scaled up and commercialized, it is essential to develop an electrode system that is more active, stable, and cost‐effective. In this study, additive‐assisted electrodeposition was utilized to fabricate a Pt/Ti electrode. Trisodium citrate (TSC) was selected as a leveling additive, and its impact on the reduction behavior of the Pt precursor and the fabricated electrode was investigated. The addition of TSC shifted the reduction potential of the Pt ion negatively due to ligand stabilization, which suppressed the nucleation and growth of the Pt deposit. A surface‐enlarged, small‐grained, and uniform Pt over‐layer with high coverage was confirmed through FE‐SEM and XRD analysis. The largest electrochemical surface of the Pt/Ti electrode with 9% TSC enhanced surface utilization and decreased charge transfer resistance. The citrate in TSC donates electrons to Pt through metal‐ligand charge transfer, increasing the electron density of Pt and facilitating the redox reaction at the electrode. The RED single cell with the Pt/Ti electrode from 9% TSC produces 0.88 W/m 2 of power density and demonstrates the long‐term operation of the RED stack.