Synthesis and Characterization of Silver/Vanadium Phosphorus Oxide/Titanium Oxide Nanostructure Composite for Chemical and Electrochemical Oxidation

Silver and vanadium phosphorus oxide are well known for catalytic activity for benzaldehyde production. Silver also enables the electrochemical oxidation of alcohol. Here, we report the catalytic characterization of Ag/VPO/TiO₂ nanostructures for selective benzaldehyde production and oxidation of alcohols. The catalyst composition includes 13.5 wt.% vanadium phosphorus oxide (VPO) and 10 wt.% silver nanoparticles embedded on titanium oxide nanotubes to form nanostructures with flake morphology. In the benzaldehyde production reaction, the mass of VPO was reduced without affecting the conversion efficiency of toluene and styrene of VPO when incorporated with TiO₂. Remarkably, the introduction of Ag to the catalyst significantly promoted the conversion of toluene and styrene, which is believed to be due to the ability of Ag to enhance the bond breaking of the H₂O₂ reagent and the transition compounds. On the other hand, the cyclic voltammetry results revealed that Ag and VPO were both active components for methanol and ethanol oxidation in alkaline medium. The results highlight the ability of Ag to improve the catalytic activity in alcohol oxidation and the benefits of using multi-site catalysts that can be applied for more than one reaction.