Electrochemical characterization of PtRu nanoparticles supported on mesoporous carbon for methanol electrooxidation

FEDERICO VIVA; MARIANO M. BRUNO *; MATIAS JOBBÁGY; HORACIO CORTI

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Lugar: Washington; Año: 2012 vol. 116 p. 4097 - 4104

1932-7447

Nanoparticles of PtRu supported on mesoporous carbon were obtained by the impregnation and reduction method with NaBH 4. The high-surface-area mesoporous carbon was obtained by carbonization of a resorcinol-formaldehyde polymer with a cationic polyelectrolyte as a soft template. Surface characterization performed by transmission electron microscopy and powder X-ray diffraction showed a homogeneous distribution and high dispersion of metal particles. The PtRu catalyst shows an electrochemical active surface area, determined by CO stripping, 45% higher than PtRu catalyst synthesized by the same method on Vulcan. This translated in a 25% increase in the methanol oxidation current as well as a lower poisoning rate and higher turnover frequency, as was assessed by cyclic voltammetry and chronoamperometry. Differential electrochemical mass spectroscopy indicated an 8% higher conversion efficiency of methanol to CO 2, demonstrating the benefits of using a mesoporous carbon as catalyst support.