Size-selected Pt Nanoparticles Synthesized via Micelle Encapsulation: Effect of Pretreatment and Oxidation State on the Activity for Methanol Decomposition and Oxidation

Abstract

The effect of pretreatment conditions on the oxidation state and activity of micelle-synthesized Pt nanoparticles supported on ZrO 2 was studied for methanol decomposition and oxidation reactions. An O 2 -pretreatment is observed to be effective for producing clean, stable, and active nanoparticles. Pt-oxide species formed during such pretreatments were found to have little influence in methanol decomposition reactions due to their tendency to reduce. However, these same species are stable during methanol oxidation and appear to take part in a Mars-van Krevelen-type of process, in which bound-oxygen (nanoparticle shell) may be replenished with oxygen from the gas phase.

Thermodynamic properties of Pt nanoparticles: Size, shape, support, and adsorbate effects

“…Further details on the sample preparation method and synthesis parameters can be found in Refs. 28,38,[41][42][43][44] and Table I. Table I.…”

Fuel Cell Electrodes From Organometallic Platinum Precursors: An Easy Atmospheric Plasma Approach

“…The oxidation state of Pt was also investigated by deconvoluting the high‐resolution Pt 4f peak, based on a method proposed by Croy . The deconvoluted spectra are represented in Figure .…”

“…Indeed, in order to take into account all the platinum components and avoid neglecting the Pt (+4) and Pt (+2) components, the whole spectral envelope of Pt on the survey scan, corresponding to the spin‐orbit doublet (Pt4f 7/2 and Pt4f 5/2 ), was considered. The sensitivity coefficient was calculated by considering the ratio of these two peak singlets areas (ratio 4f 7/2 on 4f 5/2 = 4/3 from the literature) . The XPS compositions were only used to determine the relative effect of the plasma variables on the amount of Pt deposited on the surface and not for absolute quantification.…”

Synthesis of Membrane‐Electrode Assembly for Fuel Cells by Means of (Sub)‐Atmospheric Plasma Processes

“…The high resolution scans of C1s, S2p, and Pt4f were decomposed into several peaks components, with the same FWHM for each, through convoluting Gaussian and Lorentzian profiles with respect to a 30:70 ratio. The components assignments and binding energies were based on the literature 9, 26, 27…”