CO-Terminated Pt/Au Codeposition on Titania Nanotube Arrays (TNAs)

摘要

Forming platinum monolayers on less-expensive materials is an ingenious way to enhance the mass activities for oxygen reduction reaction (ORR) and decrease the amount of this scarce and precious metal in fuel cell technology. Previously, we observed low activities of Pt catalysts deposited directly on titania nanotube arrays (TNAs). Here, we propose a gold interlayer between Pt and TiO2. The synthesis is attempted by the codeposition of Pt and Au from CO-saturated solution. The activity of the Pt/Au codeposited catalyst is higher than in the case when Pt is deposited alone. This result suggests that Au is a promising way to enhance ORR activity. The activity of this catalyst, however, is still much lower than that of the Pt monolayer on bulk gold. This is explained by the negative effects of CO, disrupting the chance of monolayer formation by preadsorption to the TNA substrate.