The low activity of the oxygen reduction reaction in polymer electrolyte membrane fuel cells is a major barrier for electrocatalysis, and hence needs to be optimized. Tuning the surface electronic structure of platinum-based bimetallic alloys, a promising oxygen reduction reaction catalyst, plays a key role in controlling its interaction with reactants, and thus affects the efficiency. Here we ...

background diatomite coated by nanoparticles of copper and zinc mixed oxides were used to investigate catalytic oxidation of carbon monoxide. objectives aim of this paper was to investigatediatomite performance as a supporting host to confine the cuo and zno nanoparticles and its catalytic activity for carbon monoxide oxidation. materials and methods the prepared catalysts were characterized by...

In this work, various 3-cyano-4-aryl-4H-pyran derivatives were prepared efficiently through a one-pot,multicomponent synthesis between aromatic aldehyde, malononitrile and acetophenone derivativesor ethyl acetoacetate using Fe3O4/EDTA magnetic nanocatalyst and ethanol as solvent. The reactionswere completed at room temperature in 10 min using 5 mg of catalyst and 2 mL of solvent to prepare1 mmo...

2,4-dinitrophenylhydrazanomethylphenol (dnphmp) was immobilized onto silicate rice husk ash to form a heterogeneous catalyst denoted as rhdnph. the elemental and edx analysis of rhdnph showed the nitrogen is incorporated into silica. the rhdnph had 154.6 m2g-1 as a specific surface area. the ft-ir clearly showed the appearance of –nh and c=n absorption band at the expected range. the tga curve ...

the magnetically recoverable fe3o4 nanoparticle and the supported brønsted acidic ionic liquid 1-methyl-3-(3-trimethoxysilylpropyl) imidazolium hydrogen sulfate (fe3o4-il-hso4) were synthesized and used as efficient magnetic catalysts for the regioselective thiocyanation of aromatic and heteroaromatic compounds at room temperature in water: ethanol. this procedure provided the target thiocyanat...

a series of x(co, mn)/tio2 catalysts (x=2–12wt.%) containing 25%co and 75%mn were prepared by the co-impregnation method. all prepared catalysts have been tested in fischer-tropsch synthesis for production of c2-c4 olefins. it was found that the catalyst containing 8wt.%(co,mn)/tio2 is an optimal catalyst for production of c2-c4 olefins. the effect of operation conditions such as the h2/co mola...

background: bromide is found naturally in groundwater and surface water. the rapid growth of industrial activities, drainage of surface runoff, and use of methyl bromide in pesticides has increased bromide discharge to the environment. disinfection of water-containing bromide causes the creation of additional products of organo-halogenated that are considered cancer-causing agents. in this stud...

In this work we present a stoichiometric reaction mechanism for the photocatalytic ethanol oxidation on TiO2(110). The reaction products are analyzed either under reaction conditions or after irradiation at lower temperatures. Water is identified as a quantitative by-product, which resides in a defect site. These water molecules cause a blocking of the defect sites which results in poisoning of...

a new type of magnetically-recoverable catalyst was synthesized by the immobilization of h3pw12o40 on the surface of silica-encapsulated -fe2o3 nanoparticles. a series of novel 1,3,5-triaryl pyrazoline derivatives has been synthesized by the reaction of chalcone and phenylhydrazine in the presence of the -fe2o3@sio2-pw12nanoparticles,  in high yields. the structures of compounds obtained were...

The solvent-free selective hydrogenation of 2-methyl-3-butyn-2-ol (MBY) to 2-methyl-3-buten-2-ol (MBE) was studied over a Pd/ZnO structured catalyst and compared to its behavior in water-assisted conditions. The catalytic behavior was correlated with the surface properties of the catalysts which were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The catalyst showed hi...