Electrocatalyst for Direct Alcohol Fuel Cells

The direct conversion of methanol in acidic environment at platinum ruthenium catalysts is the standard process in today’s direct methanol fuel cells. The high cost related to the relative high platinum loading and the user reluctance to use methanol hinder a wider market spread of this otherwise quite mature technology. Therefore catalysts for the alcohol conversion in alkaline environment were investigated allowing reducing the use of platinum group metals. In addition the use of other alcohols as fuel was investigated in both alkaline and acidic environment including high temperature polymer electrolyte fuel cell conditions. It will be shown that palladium is a good catalyst for the alcohol oxidation in alkaline environment if alloyed with other metals. It will further be shown rhodium as alloying metal can enhance ethanol oxidation in an acidic environment already at ambient temperature and even stronger at HT-PEMFC conditions.