We described the facile synthesis of sub-15 nm CeO2 nanowires for catalyzing the selective synthesis of nitrosobenzene from aniline at room temperature.

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In this work, an innovative and green oxidative process to convert renewable and abundant raw material to more value‐added fine chemicals was developed. Hydrogen peroxide, an environmentally benign oxidant, was used in Cs–exchanged lacunar Keggin heteropolyacid salts‐catalyzed oxidation reactions of the terpenic alcohols (i. e., nerol was the model molecule). The activity of most outstanding catalyst (Cs8SiW11O39) was compared with various catalysts. Epoxides and aldehydes, which are an attractive feedstock for fragrance and pharmaceutical industries were selectively obtained. Lacunar Keggin heteropolyacid salts containing cesium as the counter ion (i. e., Cs7PW11O39, Cs7PMo11O39 and Cs8SiW11O39) were easily synthesized and characterized by infrared spectroscopy, powdered X‐rays diffraction, X‐rays dispersive spectroscopy, scanning electronic microscopy, thermal analysis, porosimetry analyses, diameter and pores distribution. The influences of the main reaction variables such as catalyst concentration, the stoichiometry of the reactants and reaction temperature were evaluated. The reaction scope was successfully extended to the other terpenic alcohols. The Cs8SiW11O39 was the most active and selective lacunar salt. After five cycles of successive reuse, no loss of catalytic activity or selectivity was observed.

Barium molybdate and Barium tungstate are important materials due their photoluminescent properties and they also have catalysis and photocatalysis applications. In this work, powders of these compounds were prepared by microwave-assisted hydrothermal (MAH) method and polymeric precursor method (PPM) and their structural and optical properties were studied. Furthermore, these materials were employed as solid catalysts towards gas phase toluene oxidation reactions. X-ray diffraction confirms the purity of materials at both preparation methods and reveals a preferential growth when the powders are prepared by MAH due polymeric agents and processing using microwave, which was confirmed by Field emission scanning electron microscopy. Photoluminesce emission was attributed to the charge-transfer transitions within the [WO 4 ] 2and [MoO 4 ] 2complexes. The H 2 Temperature-Programmed Reduction (H 2 -TPR), O 2 -chemisorption and extended X-ray absorption fine structure (EXAFS) results indicated that BaWO 4 samples, compared with BaMoO 4 samples, have higher oxygen mobility and oxygen vacancies that appear as key factors for the achievement of better catalytic performances.

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