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We report the synthesis of a Ti3O5-Si (TOS) conductive metal oxide fuel cell catalyst support. TOS is prepared by doping TiO2 with Si, endowing the resultant material with enhanced electronic conductivity and durability. Support with various amounts of dopant were prepared and a 15-20 wt% Si was determined to be optimal. Intensive electrochemical durability testing shows that the TOS supports are highly stable making them highly suitable for use as a fuel cell catalyst support.

Complexes of a polar molecule (benzene trioxide) and alkali halide diatoms are predicted to form stable conformers through not only a common attachment, but also trapping the molecule between the counterions. Two possible low- and no-barrier routes of formation of such an insertion complex are identified, and stability and other properties of this and other conformers are analyzed, including polarity and charge distribution. Calculated IR spectra indicate a bright feature specific for the insertion complex, facilitating its reliable experimental detection. Isomerization of the ion-pair-trapped molecule shows a nonobvious inhibition effect (through an increased potential energy barrier) compared to the free molecule due to the reduction of its polarity in the isomerization. Formation of a flatter isomer, trioxonine, is clearly "reported" by a sharp alteration of the IR spectrum, distinguishable also from its variation for the nonreactive relaxation of the insertion complex into an attached one.

The demand for clean energy has increased significantly over the last few decades with technological advancements. Proton exchange membrane fuel cells (PEMFCs) are one such advancement with reportedly high efficiencies. Indeed, extensive research and development on all aspects regarding this technology has been done over the past two decades. However, this technology still requires more advanced electrode materials. Platinum (Pt), which exhibits high activity in the oxygen reduction reaction (ORR), is the most common and efficient electrocatalyst used in anode and cathode materials in PEMFCs. Pt is a noble metal, expensive and limited in supply. In order to maximize the efficiency of the Pt catalyst, supporting materials onto which the Pt catalyst is dispersed can play a crucial role. Traditionally, Pt nanoparticles (NPs) are dispersed onto high surface area carbonaceous materials (Pt/C) to maximize the efficiency of Pt catalyst. However, carbon is known to suffer from electrochemical degradation (ie. carbon corrosion) under harsh conditions of PEMFC, resulting in either/or Pt agglomeration and dissolution, decreasing the electroactivity of Pt catalyst. Metal oxides, such as TiO2, Nb2O5, and SiO2, have been extensively studied as alternative fuel cell catalyst supports to carbon-based materials for the ORR. Metal oxides are cheap, corrosion-resistant, and possess a large surface area. Unfortunately, these metal oxides are semi-conductive, making them impractical for fuel cell materials. Recently, there has been great interest to develop metal oxides with high electrical conductivity for fuel cell application. Among all conductive metal oxides, titanium suboxides (TixO2x-1) have shown great promise as replacements for carbon-supporting material in fuel cells. Herein, we are reporting an advanced, highly conductive metal oxide through Si-doping TiO2, yielding Ti3O5-Si (hereinafter referred to as TOS). The resulting Pt/TOS catalyst support exhibits remarkable electroactivity and durability toward the oxygen reduction reaction (ORR). Also, under advanced stability protocols including startup-shutdown and load-cycling, Pt/TOS demonstrates high stability and durability compared to commercial Pt/C (see Figure 1). This enhanced electroactivity and stability of Pt/TOS is attributed to the strong metal-support interaction (SMSI) occurring through electron donation from TOS support to the Pt nanoparticles. Figure 1

Reduced bandgap metal oxide materials are consider an alternative to carbon black supports for fuel cell catalysts. Here we report a unique N-enriched titanium nanotube suboxide doped with molybdenum (TNTS-Mo) fuel cell catalyst support. The support was prepared by the surface modification of a TNTS-Mo with a terpyridine (TPY) ligand, yielding TPY/TNTS-Mo. We have deposited Pt onto this support and evaluated its activity and stability. The Pt/TPY/TNTS-Mo catalyst was subjected to stringent accelerated stress tests (AST) designed to induce catalyst degradation similar to automotive operation and startup-shutdown conditions. The Pt/TPY/TNTS-Mo was compared with Pt/TNTS-Mo and a benchmark carbon supported Pt catalyst (Pt/C). These stability protocols confirmed that TPY modification greatly enhances the stability and durability of the Pt nanoparticles via strong metal support interaction (SMSI). In addition, the covalently attached TPY layer stabilizes the doped metal oxide supports itself, preventing changes in its surface state and composition at high potentials.

Rhenium heptoxide, a known catalyst for hydrogenation of car-boxylic acids to alcohols, forms synergistic combinations with palladium, platinum, rhodium and ruthenium catalysts. This effect is also seen at lower presures (500 psi). Synergism is also mainfest when rhenium and palladium (or rhodium) are used as supported catalysts on silica and used in a flow mode. An interaction of un-known nature between the metals suggests itself. The process is not very efficient at lower pressures giving lower conversion in the flow mode. At higher temperatures needed for higher rates, significant participation of side reactions such as decarboxylation of the acid and hydrogenolysis of the alcohol occurs yielding hydrocarbons.