Electrochemical Characterization of Free-Standing Platinum Nanoelectrode Array Using Atomic Layer Deposition for Polymer Electrolyte Fuel Cells

Abstract

This paper presents non-conventional thin-film electrodes prepared by atomic layer deposition (ALD) that are a promising alternative to conventional designs and model ionomer-free electrodes for ion conductivity studies. In the ALD process, monolayers of Pt are deposited onto the substrate by dissociative chemisorption in a self-assembling reaction. In this work, we use an ALD thermal exposure mode to deposit Pt nanostructures onto a sacrificial anodized aluminum oxide (AAO) substrates using the trimethylcyclopentadienylmethylplatinum (IV) and oxygen gas as precursors. Thermal exposure mode provides additional time for the reactions in the ALD chamber and allows higher penetration of the precursor into the substrate. We compare various ALD electrode fabrication conditions and provide detailed electrochemical analysis (electrochemical surface area, polarization curves, cyclic voltammetry) of these nanoelectrode arrays.