On-Site Characterization of Electrocrystallized Platinum Nanoparticles on Carbon and Sol−Gel Thin Film Modified Carbon Surfaces

Abstract

Platinum nanoparticles were electrocrystallized on amorphous carbon film and on sol−gel modified carbon film deposited on gold mesh grids. These Pt-modified surfaces were characterized by transmission electron microscopy and energy dispersive spectroscopy. Particles deposited on bare carbon surfaces exhibited polytetrahedral crystallographic morphology. Meanwhile, laterally dendritic growth of platinum formed by aggregation of primary particles (3−5 nm) were found on the sol−gel modified carbon surfaces. This is a new kind of morphology for electrodeposited platinum with a high specific and accessible surface area, holding great promise for Pt-catalyzed reactions. The characterization gives direct information on the microstructures of electrochemically produced particles, facilitating function and structure-correlating studies.

Electrochemical deposition of Pt nanoparticles on diamond substrates

“…In contrast, a large platinum deposition current is observed on as‐grown large grain and small grain BDD electrodes, and decays with invert square root of time and approaches that given by the Cottrell equation. The current‐time behaviour indicates an instantaneous nucleation and a planar diffusion controlled growth mechanism 16.…”

Electrochemical Applications of Silica-Based Organic−Inorganic Hybrid Materials

“…A recent investigation on electrochemically produced Pt particles on sol-gel-modified carbon film has revealed a new kind of morphology for Pt, which holds great promise for Pt-catalyzed reactions. 257 Another aspect is the exploitation of the electrochemical techniques for either probing the sol to gel to xerogel transition or characterizing the porosity of sol-gelderived materials or even evaluating the extent of interaction between a redox probe and the internal surface of the silicate. 22,153,233,248,250,[258][259][260][261][262] The general principle is based on the fact that the voltammetric response of the electrode is dependent on the apparent diffusion coefficient of the redox probe, which can be related to its mobility into the porous structure of the sol-gel material.…”

Nanofaceted Platinum Surfaces: A New Model System for Nanoparticle Catalysts

“…The catalysts are typically dispersed in a form of nanoparticles on conductive supports for a minimum loading of platinum. Although it is known that Pt nanoparticle morphologies vary greatly depending on details of synthesis, − a common feature is the prevalence of (111) and (100) surfaces, as in the case of cubooctahedra, one of the most frequently found geometries of carbon-supported platinum nanoparticles. , While molecular-level studies of electrocatalytic reactions on the nanoparticle surfaces are difficult, crystallographically well-defined surfaces of platinum, in particular, (111) and (100) surfaces, have been extensively studied as models for the nanoparticle surfaces, and a great deal of progress has been made in the past decades. However, the question of how well the individual single-crystal surfaces truly represent realistic nanoparticle surfaces still remains.…”