This work outlines improvements to the Pt catalyst durability and activity by modifying the carbon catalyst support for use in the proton exchange membrane fuel cell. Computational methods have shown that nitrogen and boron dopants to graphene supports improve the substrate. A comprehensive evaluation including two other second row dopants, Be and O, will be presented for the case where they are singly substituted into the carbon matrix. Comparison of these four doped surfaces with the undoped case will use density functional theory included in Gaussian 03. Their binding energy and activity, measured through the change in Gibbs free energy of absorption of H2 and O2 gas are shown. According to these calculations, the O-doped case provides the highest binding energy (three times higher than the undoped case) as well as the lowest change in Gibbs free energy for both gases. A quantitative evaluation including natural bond orbital, molecular orbital and AIMAll analysis shows that bonding changes in the support due to the dopant. Examining how the dopants change the local bonding in the surface will provide the ability to better select surfaces for catalyst supports.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2010: Electronics, Devices, Fabrication, MEMS, Fluidics and Computational
Published: June 21, 2010
Pages: 617 - 620
Industry sectors: Advanced Materials & Manufacturing | Sensors, MEMS, Electronics
Topic: Informatics, Modeling & Simulation