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Au nanoparticles were supported on TiO

Tungsten-based structures by microwave approach were synthesized. Four different essays were used to analyze the effect of some synthesis variables; in two of them the effect of the concentration of the solvent was studied using pure ethylene glycol and a mix of ethylene glycol and water, while the other samples the effect of the presence of reductor agent using sodium borohydride was studied. All the samples were prepared using as precursor ammonium tetrathiotungstate and sulfur in excess to incentive the growth of structures enriched in this element, for each synthesis 1 minute of irradiation was used with microwave power level of 1200 watts and frequency of 2.64 GHz. The structural, morphological, and optical characterizations were carried out with Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), infrared and uv-vis spectroscopies. By SEM, all the samples demonstrated differences in the size and morphology derivate of the modification of the experimental variables, the order of magnitude of the synthesized materials ranged from 0.01 µm until 6.5 µm, with morphologies of tetragonal prisms, flakes, irregular agglomerates or flower-like depends on the characteristics of the precursor solution. TEM lets to determine the composition of each sample, corroborated also by IR and Diffuse Reflectance spectroscopies. The four samples were used as catalysts in the study of dimethylformamide (DMF) hydrogen donor.