Cathode catalysts for direct alcohol fuel cells(DAFCs) must have high catalytic activity for the oxy-gen reduction reaction(ORR), low cost, and high tolerance to the presence of methanol or ethanol. Pt is the benchmar...Cathode catalysts for direct alcohol fuel cells(DAFCs) must have high catalytic activity for the oxy-gen reduction reaction(ORR), low cost, and high tolerance to the presence of methanol or ethanol. Pt is the benchmark catalyst for this application owing to its excellent electrocatalytic activity, but its high cost and low tolerance to the organic fuel permeating through the membrane have hindered the commercialization of DAFCs. Herein we present a facile synthesis route to obtain organic fuel-tolerant Zr- and Ta-based catalysts supported on carbon. This method consists of a simple precipitation of metal precursors followed by a heat treatment. X-ray diffraction analyses confirmed that the obtained samples were crystalline ZrO 2-x and Na2Ta8O21-x having crystallite sizes of 26 and 32 nm, respectively. The thermal treatment effectively increased the activity of the catalysts to-wards the ORR, although further optimization is necessary. Both catalysts exhibited a high tolerance to the presence of methanol with only a moderate reduction in ORR activity even at high methanol concentration(0.5 mol/L).展开更多
基金the "Mobility project Italy-Canada (Québec) n° QU13MO7"the financial support of the EU through the DURAMET Project 278054+1 种基金funding from the European Community’s Seventh Framework Programme (FP7/2011–2014) for the Fuel Cells and Hydrogen Joint Technology Initiative under grant agreement DURAMET no. 278054""Fonds de Recherche du Québec-Nature et Technologies (FQRNT)" for financial support
文摘Cathode catalysts for direct alcohol fuel cells(DAFCs) must have high catalytic activity for the oxy-gen reduction reaction(ORR), low cost, and high tolerance to the presence of methanol or ethanol. Pt is the benchmark catalyst for this application owing to its excellent electrocatalytic activity, but its high cost and low tolerance to the organic fuel permeating through the membrane have hindered the commercialization of DAFCs. Herein we present a facile synthesis route to obtain organic fuel-tolerant Zr- and Ta-based catalysts supported on carbon. This method consists of a simple precipitation of metal precursors followed by a heat treatment. X-ray diffraction analyses confirmed that the obtained samples were crystalline ZrO 2-x and Na2Ta8O21-x having crystallite sizes of 26 and 32 nm, respectively. The thermal treatment effectively increased the activity of the catalysts to-wards the ORR, although further optimization is necessary. Both catalysts exhibited a high tolerance to the presence of methanol with only a moderate reduction in ORR activity even at high methanol concentration(0.5 mol/L).