Acetic Acid Treatment of Commercial PtRu for Enhancement of Methanol Electrooxidation

摘要

Commercial carbon supported platinum-ruthenium alloy (Pt 50 Ru 50 ) was selected and employed as thetarget catalyst for the methanol electrooxidation. The performance Pt 50 Ru 50 /C in methanol oxidationcould be easily enhanced by over 3 times after it was treated in the acetic acid under hydrothermalcondition for 2 hours. The structure of this commercial carbon supported platinum-ruthenium alloy waswell characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectronspectroscopy. In addition, the data from inductively coupled plasma optical emission spectrometryconfirmed that a loss of Pt and Ru to some extent was observed and however, the molar ratio of Pt andRu was kept as well as more fine particles were obtained. Our catalytic results suggested that theoxidation of ruthenium was one key point for the enhancement of catalytic ability, possibly due to thefact that after acetic acid treatment, more ruthenium oxides were presented, which could provide moreactive hydroxyl species and thus enhanced the catalytic ability. The dissolved oxygen in the acetic acidpossibly led to the formation of Ru oxides and nearly had effect on the Pt. The present work expectedthat it could provide a new insight and facile method to increase the performance of commercialelectrocatalysts for direct methanol fuel cell.