Porous Palladium Copper Nanoparticles for Electrocatalytic Oxidation of Methanol in Direct Methanol Fuel Cells

Z-Y Shih, C-W Wang, H-T Chang
National Taiwan University, TW

Keywords: fuel cells, catalyst, nanomaterials

Summary:

A facile method has been demonstrated for the preparation of PdCu nanoparticles (NPs) with various morphologies from Pd2+ and Cu2+ reduced by ascorbate in the presence of dodecyltrimethylammonium chloride (DTAC) at 95 °C. We have found that DTAC is important to assist the growth of PdCu having high-energy surfaces through etching and capping of certain surfaces of Pd and PdCu seeds. By varying the Pd2+/Cu2+ molar ratio, different morphologies of PdCu NPs have been prepared. Cubic PdCu NPs have dominant Pd3Cu composition when prepared at a high Pd2+/Cu2+ molar ratio (20/1), while porous PdCu NPs have dominant PdCu3 composition when prepared at a low Pd2+/Cu2+ molar ratio (1/10). The content of copper atoms not only controls the morphology, but also affects the catalytic activity toward methanol oxidation reaction (MOR) in alkaline media. To the best of our knowledge, this is the first example using porous PdCu NP-modified electrodes as anodes under alkaline conditions in direct methanol fuel cells (DMFCs). With advantage of high electrochemical activity, stability, and cost effectiveness, the porous PdCu NPs hold great potential as an anode catalyst for DMFCs.