Ruthenium Nanoparticles Decorated Tungsten Oxide as a Bifunctional Catalyst for Electrocatalytic and Catalytic...

The syntheses of highly stable ruthenium nanoparticles supported on tungsten oxides (Ru-WO₃) bifunctional nanocomposites by means of a facial microwave-assisted route are reported. The physicochemical properties of these Ru-WO₃ catalysts with varied Ru contents were characterized by a variety of analytical and spectroscopic methods such as XRD, SEM/TEM, EDX, XPS, N₂ physisorption, TGA, UV-vis, and FT-IR. The Ru-WO₃ nanocomposite catalysts so prepared were utilized for electrocatalytic of hydrazine (N₂H₄) and catalytic oxidation of diphenyl sulfide (DPS). The Ru-WO₃-modified electrodes were found to show extraordinary electrochemical performances for sensitive and selective detection of N₂H₄ with a desirable wide linear range of 0.7-709.2 μM and a detection limit and sensitivity of 0.3625 μM and 4.357 μA μM^-1 cm^-2, respectively, surpassing other modified electrodes. The modified GCEs were also found to have desirable selectivity, stability, and reproducibility as N₂H₄ sensors, even for analyses of real samples. This is ascribed to the well-dispersed metallic Ru NPs on the WO₃ support, as revealed by UV-vis and photoluminescence studies. Moreover, these Ru-WO₃ bifunctional catalysts were also found to exhibit excellent catalytic activities for oxidation of DPS in the presence of H₂O₂ oxidant with desirable sulfoxide yields.