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Nanostructured Ag/WO3-TiO2 particles responding to sunlight were synthesized by dissolving silver nitrate, sodium
tungstate and tetrabutyl titanate precursors in a suitable solvent. The obtained powders were characterized by a series of
analytical methods including X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, Zeta
potential measurements and UV-vis diffuse reflectance spectra (UV-vis DRS) to demonstrate their physicochemical
properties. The as-prepared Ag/WO3-TiO2 samples were evaluated for their photocatalytic activity towards the
degradation of methylene blue (MB) under sunlight irradiations. Both silver (Ag) and tungsten (W) species were well
dispersed over TiO2 surface with less than 6.0 mol % Ag and 3.0 mol % W to Ti element and contributed to a formation
of crystalline WO3. XRD analysis particularly demonstrates the existence of mixed-phase TiO2 materials, to which the
improvement in photocatalytic activity is attributed. Besides, the light absorption of doped samples is prominent red
shifted relative to the pure TiO2 due to the synergetic effect among the components of Ag, WO3 and TiO2 in the
codoped-TiO2. The particle size of the Ag/WO3-TiO2 powders was found to be a decrease which is accompanied with
the increase of the surface area. The excellent stability and dispersity of the Ag/WO3-TiO2 powders in aqueous solution
could be attributed to the enhanced Zeta potential. On the other hand, the adsorption performances of different samples
were tested in the removal of two dyes from aqueous solution(congo red and methylene blue). The first-order adsorption
equilibrium constants were determined and the results obtained were fitted by Langmuir monolayer formation. Thus, the
Langmuir adsorption isotherm parameters were estimated from the experimental data.
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