Synthesis and Catalytic Activity of Pt Monolayer on Pd Tetrahedral Nanocrystals with CO-adsorption-induced Removal of Surfactants

Journal Article · Tue Nov 01 04:00:00 EDT 2011 · Journal of Electroanalytical Chemistry

DOI:https://doi.org/10.1016/j.jelechem.2011.07.008· OSTI ID:1041629

Gong, K; Vukmirovic, M B; Ma, C; Zhu, Y; Adzic, R R

We synthesized the Pt monolayer shell-Pd tetrahedral core electrocatalysts that are notable for their high activity and stable performance. A small number of low-coordination sites and defects, and high content of the (1 1 1)-oriented facets on Pd tetrahedron makes them a suitable support for a Pt monolayer to obtain an active O{sub 2} reduction reaction (ORR) electrocatalyst. The surfactants, used to control size and shape of Pd tetrahedral nanoparticles, are difficult to remove and cause adverse effects on the ORR. We describe a simple and noninvasive method to synthesize high-purity tetrahedral Pd nanocrystals (TH Pd) by combining a hydrothermal route and CO adsorption-induced removal of surfactants. Poly(vinylpyrrolidone) (PVP), used as a protecting and reducing agent in hydrothermal reactions, is strongly bonded to the surface of the resulting nanocrystals. We demonstrate that PVP was displaced efficiently by adsorbed CO. A clean surface was achieved upon CO stripping at a high potential (1.0 V vs RHE). It played a decisive role in improving the activity of the Pt monolayer/TH Pd electrocatalyst for the ORR. Furthermore, the results demonstrate a versatile method for removal of surfactants from various nanoparticles that severely limited their applications.

• Research Organization: BROOKHAVEN NATIONAL LABORATORY (BNL)
• Sponsoring Organization: USDOE SC OFFICE OF SCIENCE (SC)
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1041629
• Report Number(s): BNL--96977-2012-JA; KC0302010
• Journal Information: Journal of Electroanalytical Chemistry, Journal Name: Journal of Electroanalytical Chemistry Journal Issue: 1 Vol. 662; ISSN 1572-6657
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CARBON MONOXIDE
DEFECTS
ELECTROCATALYSTS
OXYGEN
PERFORMANCE
PLATINUM
REDUCING AGENTS
REMOVAL
SHAPE
SURFACTANTS
SYNTHESIS