Probe beam deflection studies of nanostructured catalyst materials for fuel cells

G. GARCIA; M.M. BRUNO; G.PLANES; J.L. RODRIGUEZ; C.A. BARBERO; E.PASTOR

PHYSICAL CHEMISTRY CHEMICAL PHYSICS

royal society of chemistry

Lugar: londres; Año: 2008 vol. 10 p. 6677 - 6685

1463-9076

Probe beam deflection (PBD) techniques, both as cyclic voltadeflectometry (CVD) andchronodeflectometry (CD), were applied for the first time to the study of the electrochemistry ofnanostructured Pt materials which are commonly used as electrocatalysts in fuel cells. Theelectrochemical surface reactions, including faradaic processes, double layer charging and specificanion adsorption were easily detected. Quantitative analysis of the chronodeflectometric datamade possible to elucidate the dynamics of double layer charging in such materials and todetermine the potential of zero charge (pzc) of the metal present either as a monolithicmesoporous material or as metal nanoparticles supported on carbon. The electro-oxidation ofCO, adsorbed on nanostructured Pt, was also studied by CVD and CD being able to detect theformation of CO2 and H3O+ related with the nucleation and growth process which controls therate of CO stripping. The interplay of Pt oxide formation and COad electrooxidation, both inpotential and time, was detected indicating possible application of the technique to otherelectrocatalysts.