Atomic Layer Deposition of Bimetallic Nickel/Nickel Oxide and Platinum Catalysts on Alumina for Electrochemical Devices

Platinum-nickel bimetallic, often in the form of nanoparticles, is one of the most effective catalysts for both the hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR) in hydrogen fuel cells. Issues arise with use of nanoparticles due to their aggregation at higher temperatures, such as when used in phosphoric acid fuel cells. With larger particles, expensive bulk atoms go unutilized which increases the cost of the device and decreases its lifetime.  Atomic layer deposition (ALD) is a scalable deposition method that can create materials with tunable sizes.  Using either oxygen or hydrogen as a precursor, nickel particles and nickel oxide films were grown on alumina using ALD.  Then platinum was deposited using ALD on both materials using either the oxygen and hydrogen chemistry.  These catalysts were investigated for HOR activity and were inspected using Transmission Electron Microscopy (TEM), and Inductively Coupled Plasmon Mass Spectroscopy (ICP-MS).