Fuel cells are electrochemical cells that convert chemical energy into electrical energy with efficiencies up to 80%; they are a promising potential replacement for internal combustion engines in automobiles. However, carbon monoxide poisoning of the anode catalyst is a major obstacle preventing their use. The ideal solution is to remove CO from the H2 feed gas before it reaches the catalyst. The present project develops novel external metal/graphene membranes capable of capturing CO before it enters the cell. These membranes must have strong binding to CO and weak binding to H2. Density functional theory calculations showed that CO has the strongest binding to Pt/C followed closely by Ni/C. Of these metals, nickel has a notably weaker interaction with H2. Addition of boron, nitrogen or oxygen dopants to the carbon surface decreases CO binding and causes H2 binding to become negligible. Recent experimental studies measured the potential desorption of CO and H2 from platinum and nickel nanoparticles deposited on several carbon substrates. The present paper describes the experimental analysis of these systems and compares results with computed binding energy strength of CO and H2 to Pt/C and Ni/C. In addition, influence of the carbon substrate on metal catalytic properties is determined.
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2011: Advanced Materials, CNTs, Particles, Films and Composites
Published: June 13, 2011
Pages: 734 - 737
Industry sectors: Advanced Materials & Manufacturing | Energy & Sustainability
Topics: Energy Storage