Synthesis of Pt-Adsorbed WO₃ Nanostructures and Their Surface Reactivity Enhancement Properties

WO₃ nanorods with a thickness of tens of nanometers and a length of tens of micrometers were synthesized by a gas phase transport mechanism. During the synthesis process, no catalysts were used for nucleation and growth of WO₃, and it could be produced simply by the transport of reactive gases to the Si substrate surface and their reaction. By additionally adsorbing Pt nanoparticles onto the WO₃ surface, the reactivity toward both CO, a reducing gas, and NO₂, an oxidizing gas, was improved at 300 °C. The remarkable gas sensor responses in both oxidizing and reducing gases imply that the defects formed on the surface of the Pt-adsorbed WO₃ nanostructures have a greater influence. In addition, minor causes such as the interface of Pt-WO₃ and the electron affinity between target gas and WO₃ were also investigated.