Catalytic Carbon Monoxide Oxidation over Size-Controlled Pt Nanoparticles in the Gas Phase and Elevated Temperatures

E.A BARANOVA; P. VERNOUX; L. LIZARRAGA; E. OBEID; R.J. ISAFAN; H. DOLE

Montreal

Encuentro; 219th Electrochemical Society Meeting; 2011

Electrochemical Society

Electrochemical Promotion of catalysis (EPOC) or Nonfaradaic Electrochemical Modification of Catalytic Activity (NEMCA) effect is a recently discovered concept, which can be applied to modify both the activity and the selectivity of a catalyst [1]. The controlled variation in the catalyst-electrode potential of metal or metal oxide catalyst supported on solid electrolytes is responsible for considerable changes in catalytic activity and selectivity. The major obstacle towards commercialization of EPOC is the low dispersion of the thick (typically 0.2 to 10 um) porous catalyst films used in most of the previous electrochemical promotion studies. Volatile organic compounds (VOCs), present in buildings or cars, are wide-ranging classes of chemicals and currently over 300 compounds are considered as VOCs by US Environmental Protection Agency (EPA). Their release has widespread environmental implications, and has been linked to the increase in photochemical smog, the depletion of atmospheric ozone and the production of ground-level ozone. The removal of formaldehyde and carbon monoxide is vital for improving indoor air quality and human being?s health due to a carcinogenic risk. In the present work, we studied oxidation of carbon monoxide, as a model reaction, on Pt nanoparticles of the well controlled mean sizes: 6.5, 3.0 and 1.5 nm deposited on yttria-stabilized zirconia (YSZ, an O2- ionic conductor). The objective is to investigate the influence of Pt size on the thermal migration of anions from the support toward the Pt surface [3]. Catalytic performances were compared with those obtained with the carbon black as a support.