Hybrid Catalyst For Oxidation Research Articles

Polyoxometalate–Reduced Graphene Oxide Hybrid Catalyst: Synthesis, Structure, and Electrochemical Properties

The deposition of polyoxometalate (POM) on chemically reduced graphene oxide sheets was carried out through electron transfer interaction and electrostatic interaction between POM and graphene sheets to make a heterogeneous catalyst in aqueous media. Well dispersed individual phosphomolybdic acid (PMo) clusters were observed by electron microscopy and atomic force microscopy measurements. The interaction between polyoxometalate and the graphene sheet was confirmed by using various spectroscopic methods such as FT-IR, UV-vis, and Raman. The UV-visible, IR, and cyclic voltammetry results revealed alteration of the electronic structure of deposited PMo as a result of strong interaction with the graphene oxide surface. Electrochemical properties of the PMo-rGO catalyst were investigated in an aqueous acidic electrolyte. The hybrid catalyst showed enhanced electro-oxidation of nitrite compared with pure homogeneous PMo and rGO.

Porous silica supported Co2+-tetrachlorophthalocyanine (CoPcCl-APTES@SiO2): a novel and recyclable organic–inorganic hybrid catalyst for eco-friendly oxidation of secondary alcohols

A novel, selective and recyclable cobalt based catalyst has been synthesized by covalent grafting of Co2+-tetrachlorophthalocyanine (CoPcCl) onto porous silica functionalized with 3-aminopropyltriethoxysilane (APTES), and the resulting organic–inorganic hybrid porous material was found to be highly effective catalyst for peroxidative oxidation of secondary alcohols. The porous material was characterized by elemental analysis, diffuse reflectance UV–Visible spectroscopy, 13C CPMAS and 29Si CPMAS NMR spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), BET surface area analysis, Energy dispersive X-ray fluorescence (ED-XRF), Fourier transform Infrared (FT-IR) and Atomic absorption spectroscopy (AAS) techniques. High turnover frequency, mild reaction conditions, high selectivity for ketones, and easy recovery and reusability of the catalyst renders the present protocol highly essential to address the industrial needs and environmental concerns.

Silica-supported molybdenum complex: A novel, selective and reusable organic–inorganic hybrid catalyst for eco-friendly oxidation of sulfides and olefins

A novel, highly efficient and reusable molybdenum based catalyst has been synthesized by covalent grafting of 2,6-diacetylpyridine-monosalicyloylhydrazone onto functionalized silica followed by complexation with MoO2(acac)2, and the resulting organic–inorganic hybrid material was found to be highly effective catalyst for oxidation of various sulfides and olefins to their corresponding sulfoxides/sulfones and epoxides, respectively. The catalyst was characterized by elemental analysis (CHN), diffuse reflectance UV–Vis, 13C CPMAS NMR spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET surface area analysis, energy dispersive X-ray fluorescence (ED-XRF), Fourier-transform infrared (FT-IR) and atomic absorption spectroscopy (AAS). Mild reaction conditions, high turnover frequency, high selectivity, easy recovery and reusability of the catalyst render the present protocol very useful to address the industrial needs and environmental concerns.

Ultra-long Pt nanolawns supported on TiO2-coated carbon fibers as 3D hybrid catalyst for methanol oxidation

In this study, TiO2 thin film photocatalyst on carbon fibers was used to synthesize ultra-long single crystalline Pt nanowires via a simple photoreduction route (thermally activated photoreduction). It also acted as a co-catalytic material with Pt. Taking advantage of the high-aspect ratio of the Pt nanostructure as well as the excellent catalytic activity of TiO2, this hybrid structure has the great potential as the active anode in direct methanol fuel cells. The electrochemical results indicate that TiO2 is capable of transforming CO-like poisoning species on the Pt surface during methanol oxidation and contributes to a high CO tolerance of this Pt nanowire/TiO2 hybrid structure.

ChemInform Abstract: Novel 2,2,6,6‐Tetramethylpiperidine 1‐Oxyl—Iodobenzene Hybrid Catalyst for Oxidation of Primary Alcohols to Carboxylic Acids.

AbstractA variety of primary and secondary alcohols is oxidized to carboxylic acids with mostly small amounts of aldehydes using the hybrid catalysts (I) and large excess of peracetic acid.

Novel 2,2,6,6‐Tetramethylpiperidine 1‐Oxyl–Iodobenzene Hybrid Catalyst for Oxidation of Primary Alcohols to Carboxylic Acids

AbstractNovel bifunctional hybrid‐type catalysts bearing 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) and iodobenzene moieties (1a and 1b) were developed and used for the environmentally benign oxidation of primary alcohols to carboxylic acids. Reaction of primary alcohols 2 with a catalytic amount of 1 in the presence of peracetic acid as a co‐oxidant under mild conditions gave the corresponding carboxylic acids 3 in excellent yields.