Platinum/Mesoporous WO₃ as a Carbon-Free Electrocatalyst with Enhanced Electrochemical Activity for Methanol Oxidation

Abstract

A new type of carbon-free electrode catalyst, Pt/mesoporous WO3 composite, has been prepared and its electrochemical activity for methanol oxidation has been investigated. The mesoporous tungsten trioxide support was synthesized by a replicating route and the mesoporous composties with Pt loaded were characterized by using X-ray diffraction (XRD), nitrogen sorption, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) techniques. Cyclic voltammetry (CV), line scan voltammetry (LSV) and chronoamperometry (CA) were adopted to characterize the electrochemical activities of the composites. The mesoporous WO3 showed high surface area, ordered pore structure, and nanosized wall thickness of about 6-7 nm. When a certain amount of Pt nanoparticles were dispersed in the pore structure of mesoporous WO3, the resultant mesostructured Pt/WO3 composites exhibit high electro-catalytic activity toward methanol oxidation. The overall electro-catalytic activities of 20 wt % Pt/WO3 composites are significantly higher than that of commercial 20 wt % Pt/C catalyst and are comparable to the 20 wt % PtRu/C catalyst in the potential region of 0.5-0.7 V. The enhanced electro-catalytic activity is attributed to be resulted from the assistant catalytic effect and the mesoporous structure of WO3 supports.

A Highly Stable Anode, Carbon‐Free, Catalyst Support Based on Tungsten Trioxide Nanoclusters for Proton‐Exchange Membrane Fuel Cells

“…Previous studies have shown that Pt and Pt-Ru catalysts supported on WO 3 have a high activity towards the electrooxidation of methanol and hydrogen. [20][21][22][23][24] Cui at el. [24] synthesized the meso-structured WO 3 as an anode catalyst support and they found that the catalyst showed high electrocatalytic activity for hydrogen electrooxidation and exhibited much improved resistance to Durability is an important issue in proton-exchange membrane fuel cells (PEMFCs).…”

Investigating the Influence of Au Nanoparticles on Porous SiO2–WO3 and WO3 Methanol Transformation Catalysts

“…Oxidations of olefins to epoxides are also readily accessible in the presence of WO 3 catalysts and peroxide, [23][24][25][26] and semiconducting WO 3 serves as a very efficient catalyst in photochemical and electrochemical oxidation reactions. [27][28][29] Despite success in these applications, catalysts containing mostly WO 3 have been limited in gasphase thermal oxidations of alcohols with O 2 or air as the only oxidant. The poor alcohol oxidation reactivity of pure WO 3 may be attributed to the non-labile lattice oxygen atoms of WO 3 under catalytic conditions that favor dehydration.…”

Advances in Ceramic Supports for Polymer Electrolyte Fuel Cells

“…Tungsten oxides (predominantly WO3) were studied for quite a long time as a catalyst for DMFC and showed high catalytic activity toward methanol oxidation reaction, possibly due to the formation of tungsten bronzes favoring the dehydrogenation of methanol, and a synergistic effect leading to CO tolerance [56][57][58]. Park et al [59] showed excellent performance for the use of porous tungsten oxide in thin film fuel cells and also showed good stability in sulfuric acid.…”