Performance Enhancement of Polymer Electrolyte Membrane Fuel Cells with Cerium Oxide Interlayers Prepared by Aerosol-Assisted Chemical Vapor Deposition

Abstract

In this study, the performance and durability of a Pt/CeOx catalyst membrane electrode assembly (MEA) fabricated by chemical vapor deposition and sputtering using aerosols were investigated for use in a polymer electrolyte membrane fuel cell (PEMFC). The cost burden of Pt-based catalysts and the degradation of performance and durability owing to corrosion of the carbon support under certain conditions limit the commercialization of PEMFCs. To solve these problems, the development of Pt alloy catalysts (Pt–Co, Pt–Ni, and Pt–Fe), Pt-based core–shell catalysts (Pt–TiO2 and Pt–CeO2), Pt bimetallic catalysts (Pt–Pd, Pt–Ru, and Pt–Sn), and Pt-based nanocomposites (Pt/graphene and Pt/carbon nanotubes) is being actively researched. Inserting a CeOx interlayer between Pt and carbon has three advantages: (i) oxygen supply to Pt due to CeOx interlayer’s ability to store oxygen improves catalyst utilization, (ii) improves the dispersibility of Pt, and (iii) solves the problem of performance and durability degradation by preventing the formation of reactive intermediates. For the deposition of ceria, the aerosol-assisted chemical vapor deposition process, which is performed at atmospheric pressure and can be uniformly deposited over a wide area with spray-based precursor delivery characteristics, was applied. The performance and electrochemical surface area of the Pt/CeOx MEA were determined using I–V measurements and cyclic voltammetry, and the durability of the Pt/CeOx MEA was analyzed using electrochemical impedance spectroscopy and an accelerated degradation test. As a result, when the Pt/CeOx on the gas diffusion layer (GDL) MEA was used, the performance improved by 46% compared to that of Pt on the GDL.