Magneli-type tungsten oxide nanorods as catalysts for the selective oxidation of organic sulfides

Abstract

Selective oxidation of thioethers is an important reaction to obtain sulfoxides as synthetic intermediates for applications in chemical industry, medicinal chemistry and biology or the destruction of warfare agents. The...

Modulating the Catalytic Properties of Polyoxovanadates with Transition-Metal-Complex Units for Selective Oxidation of Sulfides

“…However, the operation of the greener oxidants generally requires the use of a catalyst. Various catalysts have been explored, including metal oxides, , nanoparticles of noble metals, , metal-functionalized composite materials, − polyoxometalates, , and metal–organic frameworks (MOFs), − among which vanadate (V–O)-based ones stand out because of their high activity, ready availability, and low costs. The initial efforts in this vein concentrated on the catalytic use of V 2 O 5 , with which the oxidation of sulfides using tert -butyl hydroperoxide (TBHP), H 2 O 2 , cumene hydroperoxide, or O 2 as oxidants was achieved.…”

Lithium confinement and dynamics in hexagonal and monoclinic tungsten oxide nanocrystals: a 7Li solid state NMR study

“…1 The number of examples where band theory alone can provide an adequate property description is limited and mostly confined to compounds of the 4d and 5d series such as A x WO 3 or the Magneli-type phases M n O 3n−2 . 2 Tungsten trioxide has long been studied for its structural, electronic, and electrochromic properties, and it has become a hot topic in fields like photoluminescense, 3 NIR light-shielding, 4,5 plasmonics, 6,7 thermoelectrics, [8][9][10][11] superconductivity, 1,12,13 gas sensing, 14 supercapacitors, 15 batteries, [16][17][18] catalysis 19 or photocatalysis, 20 and for water splitting devices 21 and solar cells. 22,23 Tungsten trioxide (WO 3 ) has a ReO 3 -type structure with corner-sharing WO 6 octahedra.…”

“…36,37 The structural channels arising from the 3D corner-sharing octahedra are large enough to accommodate guest cations ( protons, ammonium and alkali ions) to form the so-called "tungsten bronzes". [38][39][40][41] Other than in tetrahedral network structures with redox-inert elements (e.g., Si, Al), 42 the tung-sten oxides impart distinct substitutional 43 and redox 19 properties to these octahedral transition metal network structures. Fast electron transfer between the valence states of adjacent W 5+ and W 6+ sites makes tungsten bronzes electrically conducting (or semiconducting), intensely colored, and by varying the oxidation state, sequences of solid phases occur, sometimes with large homogeneity ranges.…”