Synthesis of Mesoporous Pt Films with Tunable Pore Sizes from Aqueous Surfactant Solutions

Abstract

Platinum (Pt) is widely used as battery electrodes, catalysts for chemicals, and catalysts for exhaust gas decomposition in industries. Increasing need and very limited supply of rare Pt is a serious problem in the world. Here, we propose new synthetic way for reducing the use of Pt in a catalytic system by increasing the surface area and modifying the Pt surface structure. Several types of mesoporous Pt films with different pore sizes ranging from 5 to 30 nm are prepared by electrochemical plating in aqueous surfactant solutions. The mesopore walls are composed of connected Pt nanoparticles with around 3 nm in diameter. The Pt atomic crystallinity is coherently extending across over several Pt nanoparticles, showing a large number of atomic steps, which can accelerate methanol oxidation reaction. As a result of a high surface area and unique Pt surface, our mesoporous Pt film exhibits high potentiality as a superior electrocatalyst.

Electrochemical Synthesis of Mesoporous Pt Nanowires with Highly Electrocatalytic Activity toward Methanol Oxidation Reaction

“…From the highly magnified SEM image (Figure 1b), the average pore size is estimated to be 6-7 nm, which is consistent with previously reported data on similar system [26]. The well-distributed mesoporous structures are further confirmed from the high-angle annular dark-field scanning TEM (HAADF-STEM) images (Figure 1d).…”

“…Also, the concave surface on the mesopores can provide abundant catalytically active sites for the reactions, which is totally different from the convex surfaces usually observed in nanoparticles [26,[29][30][31]. Recently, Fujita et al have reported that the concave Au surfaces caused a higher catalytic activity toward CO oxidation [32].…”

“…Recently, we have developed a novel 'electrochemical micelle assembly' soft-templating method which is a facile and effective route to obtain mesoporous metals with controlled pore sizes [18,26,27]. This micelle assembly allows good control over the shape of Pt-based materials, e.g.…”

“…This micelle assembly allows good control over the shape of Pt-based materials, e.g. 0D nanoparticles, 1D NWs, and 2D films [18,[26][27][28].…”

Platinum Nanoparticles Encapsulated in Carbon Microspheres: Toward Electro-Catalyzing Glucose with High Activity and Stability

“…In the past few years, several materials including noble metals (Pt, Pd, Au, et al) [6,9-11], non-precious metals (Ni, Cu, et al) [12][13][14], and non-metallic electrodes [15,16] have been explored to promote this sluggish kinetics-controlled reaction. Among these materials, Pt is generally believed to be the most effective and stable catalyst candidate [17][18][19]. However, the following two critical issues seriously hinder the industrial use of Pt-based catalysts on a large scale: first, the glucose oxidation reaction occurred on conventional Pt electrodes can not produce sufficient faradic current responses for various utilizations; second, the catalytic activity of Pt materials is easily poisoned by species such as chloride ions.…”