Accession Number : ADA577895


Title :   The Role of Non-Conventional Supports for Single-Atom Platinum-Based Catalysts in Fuel-Cell Technology: A Theoretical Surface Science Approach


Descriptive Note : Final rept. 30 Jan 2012-29 jan 2013


Corporate Author : YONSEI UNIV SEOUL (REPUBLIC OF KOREA)


Personal Author(s) : Soon, Aloysius


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a577895.pdf


Report Date : 05 Feb 2013


Pagination or Media Count : 18


Abstract : As a first step towards a microscopic understanding of single-Pt atom-dispersed catalysts on non-conventional TiN supports, we present density-functional theory (DFT) calculations to investigate the adsorption properties of Pt atoms on the pristine TiN(100) surface, as well as the dominant influence of surface defects on the thermodynamic stability of platinized TiN. Optimized atomic geometries, energetics, and analysis of the electronic structure of the Pt/TiN system are reported for various surface coverages of Pt. We find that atomic Pt does not bind preferably to the clean TiN surface, but under typical PEM fuel cell operating conditions, i.e. strongly oxidizing conditions, TiN surface vacancies play a crucial role in anchoring the Pt atom for its catalytic function. Whilst considering the energetic stability of the Pt/TiN structures under varying N conditions, embedding Pt at the surface N-vacancy site is found to be the most favorable under N-lean conditions. Thus, the system of embedding Pt at the surface N-vacancy site on TiN(100) surface could be a promising catalyst for PEM fuel cells.


Descriptors :   *FUEL CELLS , ADSORPTION , ATOMS , COMPUTATIONS , DEFECTS(MATERIALS) , ELECTRODES , ELECTRONICS , METHODOLOGY , OPTIMIZATION , OXIDATION , TIN


Subject Categories : Electrochemical Energy Storage


Distribution Statement : APPROVED FOR PUBLIC RELEASE