AVS 63rd International Symposium & Exhibition
    Surface Science Tuesday Sessions
       Session SS2+AS+HC+NS-TuM

Paper SS2+AS+HC+NS-TuM3
Role of the Strong Metal Support Interaction on the Catalytic Activity of Platinum Deposited on TiO2 Supports

Tuesday, November 8, 2016, 8:40 am, Room 104E

Session: Nanostructures: Growth, Reactivity, and Catalysis
Presenter: R.Paul Hansen, University at Albany-SUNY
Authors: R.P. Hansen, University at Albany-SUNY
R.S. Phillips, University at Albany-SUNY
E.T. Eisenbraun, SUNY Polytechnic Institute
C.A. Ventrice, Jr., SUNY Polytechnic Institute
Correspondent: Click to Email
Several roadblocks prevent the large-scale commercialization of hydrogen fuel cells, including the stability of catalysts and their substrates and the high cost of the Pt involved in the oxygen reduction reaction (ORR). The former of these problems can be solved by replacing the traditional carbon support with a conductive metal oxide such as reduced TiO2, which will not easily corrode and should result in longer lasting fuel cells. The Pt is necessary in the cathode of the fuel cell to overcome the slow kinetics of the ORR. In this study, Pt was deposited either by atomic layer deposition (ALD) or physical vapor deposition (PVD). The typical size of the Pt islands that were grown using these deposition techniques was 5-8 nm. One factor that can inhibit the catalytic activity of a metal catalyst on a metal oxide is the strong metal support interaction (SMSI). This is where a metal on a reducible metal oxide can be encapsulated by a layer of the metal oxide support material at elevated temperatures. The processing of materials through atomic layer deposition can exceed this temperature. The TiO2 substrates used in this study were either grown by ALD, which results in a polycrystalline anatase film, or were single-crystal rutile TiO2(110) samples prepared in ultra-high vacuum (UHV). The Pt/TiO2 samples were tested electrochemically using cyclic voltammetry (CV) to determine the level of catalytic activity. To determine the effect of the SMSI interaction on the catalytic activity of the PVD grown samples, CV was performed on samples that were annealed in high vacuum after Pt deposition. Additional characterization was performed with scanning electron microscopy (SEM), Auger electron spectroscopy (AES), x-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectrometry (RBS), and four point probe analysis.