Oxygen reduction over dealloyed Pt layers on glancing angle deposited Ni nanostructures

Ni nanopillar structures were fabricated on glassy carbon electrodes (NiGLAD/GC) using glancing angle deposition (GLAD). Thin, conformal layers of Pt were deposited by a rotating substrate, self-limiting, high current density galvanostatic deposition to form NiGLAD{Pt}/GC deposits. The Pt loading in the NiGLAD{Pt}/GC deposits was systematically varied by interrupting the deposition at various coverages, and the series of the NiGLAD{Pt}/GC deposits were evaluated as catalysts for the oxygen reduction reaction (ORR) in O2 saturated, 0.1 M HClO4 at room temperature. The optimum amount of Pt (initial wt. ratio ∼ Pt0.22Ni0.78) was deposited over 800 to 1500 seconds. These deposits, after dealloying, were about 30 times more active by mass and by surface area than a {Pt}/GC electrode prepared by deposition of Pt onto GC under the same conditions.