High-Activity Mesoporous Pt/Ru Catalysts for Methanol Oxidation

E. A. FRANCESCHINI; M. M. BRUNO; F. J. WILLIAMS; F. A. VIVA; H. R. CORTI

ACS APPLIED MATERIALS & INTERFACES

AMER CHEMICAL SOC

Lugar: Washington; Año: 2013 vol. 5 p. 10437 - 10444

1944-8244

High activity mesoporous Pt/Ru catalysts with 2D-hexagonal structure weresynthesized using a triblock poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethyleneoxide) copolymer (Pluronic F127) template. The normalized mass activities for the methanoloxidation reaction (MOR) of the Pt/Ru catalysts with a regular array of pores is higher thanthose reported for nanoparticulated Pt/Ru catalysts. Different kinetic parameters, as Tafelslope and activation energy, were obtained for the MOR on the mesoporous catalysts. Resultsindicated that catalysts performance depends on pore size. Mass activities and the CO2conversion efficiency for large pore size mesoporous catalysts (10 nm) are greater than thosereported for smaller pore size mesoporous catalysts with similar composition. The effect ofpore size on catalysts performance is related to the greater accessibility of methanol to theactive areas inside large pores. Consequently, the overall residence time of methanol increasesas compared with mesoporous catalyst with small pores.