Effect of KOH Activation on Carbon Supports for Methanol Oxidation of PtRu/CBs/MWNTs Catalysts

摘要

PtRu catalysts deposited on carbon supports have been extensively studied as promising anode catalysts for direct methanol fuel cells (DMFCs). To develop performance of DMFCs, the ideal carbon supports should have suitable characteristics, such as high electrical conductivity, large active surface area, and low resistance. In this work, multi-walled carbon nanotubes (MWNTs) and carbon blacks (CBs) used as carbon supports were modified by KOH activation in order to improve these properties. The PtRu deposited on CBs/MWNTs were prepared by impregnation method and characterized by BET, X-ray diffraction (XRD), and transmission electron microscopy (TEM). Electrochemical behaviors of the catalysts for methanol oxidation were investigated by cyclic voltammetry (CV). As a result, it was found that KOH activation could influence on properties of the CBs/MWNTs, resulting that the size and loading content of PtRu deposited on the modified carbon supports could be changed. In addition, electro-catalytic activity of the catalysts was enhanced with changed properties of the carbon supports. Consequently, it was thus considered that the properties of the carbon supports could significantly affect the methanol oxidation of anodic electrocatalysts in DMFCs.