Particle Size Effect: Ru-Modified Pt Nanoparticles Toward Methanol Oxidation

Abstract

Ru-modified Pt nanoparticles of various sizes on platelet carbon nanofiber toward methanol oxidation were investigated in terms of particle size effect. The sizes of Pt nanoparticles, prepared by polyol method, were in the range of 1.5-7.5 nm and Ru was spontaneously deposited by contacting Pt nanoparticles with the Ru precursor solutions of 2 and 5 mM. The Ru-modified Pt nanoparticles were characterized using transmission electron microscopy, X-ray photoelectron spectroscopy and cyclic voltammetry. The methanol oxidation activities of Ru-modified Pt nanoparticles, measured using cyclic voltammetry and chronoamperometry, revealed that when the Pt particle size was less than 4.3 nm, the mass specific activity was fairly constant with an enhancement factor of more than 2 at 0.4 V. However, the surface area specific activity was maximized on Pt nanoparticles of 4.3 nm modified with 5 mM Ru precursor solution. The observations were discussed in terms of the enhancement of poison oxidation by Ru and the population variation of Pt atoms at vertices and edges of Pt nanoparticles due to selective deposition of Ru on the facets of (111) and (100).

Shape‐controlled Electrodeposition of Standing Pt Nanoplates on Gold Substrates as a Sensor Platform for Nitrite Ions

“…Noble metal nanoparticles (NPs) fascinate countless benefits due to their distinctive catalytic activities associated with their chemical and physical properties, which depends on their size and shape . Among the noble metals, platinum (Pt) NPs are dominant due to its potential applications in fuel cells as a catalyst, such catalyst's performance are often tunable by varying the size, shape, and alloying with the second metals such as gold (Au), palladium (Pd), and ruthenium (Ru) . Among the different morphologies of Pt, sheets/plates attracts wide attention due to their latent applications in various fields .…”