ALD of Pt nanotube arrays supported on a carbon fiber cloth as a high-performance electrocatalyst for methanol oxidation†
Slow oxidation kinetics of methanol and CO poisoning of the Pt-based catalysts are still the two major challenges faced by direct methanol fuel cells. Herein, we demonstrate the fabrication of ordered hollow Pt nanotube arrays supported on a carbon fiber cloth by atomic layer deposition (ALD) with ZnO nanorod arrays as sacrificial templates. The ordered Pt nanotube arrays (NTAs) as anodes presents improved methanol electro-oxidation performance (815 mA mg−1) and superior CO tolerance in contrast to that of the commercial Pt/C catalysts (275 mA mg−1). The significantly improved performance could be attributed to the 3D porous hollow nanotubes structure containing numerous small Pt nanoparticles, which can provide abundant reactive sites for methanol oxidation, as a result of improving the electro-catalytic activity and directly oxidizing the active intermediate to CO2 instead of CO.