Fuel Cell Vehicles (FCVs) can reduce source-to-wheel greenhouse emissions by 15-45% compared to internal combustion engine vehicles. Despite the promise of FCVs, significant cost-reduction is needed for mass adoption. Combining maximum platinum utilization with enhanced durability of the electrocatalyst layers is the goal of several contemporary research and development efforts. In this context, nanostructured thin films (NSTF) comprising platinum atomic overlayers on conductive, non-carbon-based support have emerged as a design paradigm. We propose to use inkjet-printed nanostructures (Parmar et al. (2014)) as substrates for platinum electrodeposition to fabricate such NSTFs.

Herein, we report the potentiostatic pulsed electrodeposition of platinum overlayers onto thin foils of silver, gold, or gold-silver alloys, thereby building on our previous study (Agrawal et al., (2021)). We will present an analysis of the current signals obtained during the pulsed deposition of platinum overlayers. We will describe the detailed characterization of such thin films using ICP-OES, XPS, FESEM and four-probe conductivity measurements to understand the evolution of platinum loading, oxidation state, structural changes, and conductivity after various stages of durability analysis. We have identified the processing conditions needed to yield low platinum loaded electrocatalytically active thin films with < 40 % ECSA loss after 30,000 ex-situ durability cycles to meet the Department of Energy (DOE) target for durability.

Keywords: Nanostructured Thin Film Electrodes (NSTFs), Platinum overlayers, Durability, Gold-Silver alloy

References:

1. S.K. Parmar and V. Santhanam, Curr.Sci., 107, 262-269 (2014)
2. K. Agrawal, S. Chaudhary, D. Parvatalu, and V. Santhanam, ECS Trans., 104, 379–386 (2021)