Room-temperature volatile organic compounds sensing based on WO3 center dot 0.33H(2)O, hexagonal-WO3, and their reduced graphene oxide composites

Author(s)

Perfecto, T. M. ; Zito, C. A. ; Volanti, D. P.

• Document type: Journal article
• Source: RSC ADVANCES; v. 6, n. 107, p. 105171-105179, 2016.
• Web of Science Citations: 14

Abstract

Nanostructured orthorhombic WO3 center dot 0.33H(2)O, hexagonal h-WO3 and their RGO composites (RGO-WO3 center dot 0.33H(2)Oand RGO-h-WO3) are reported for the purpose of efficient sensing of volatile organic compounds (VOCs) (e.g. acetone, methanol, benzene, toluene, and m-xylene). The materials were prepared at 140 degrees C by one-pot microwave-assisted hydrothermal (MAH) synthesis from Na(2)WO(4 center dot)2H(2)O and graphite oxide (in the case of composite) suspension in acid medium, without using any reducing, organic, or capping reagent. A three-dimensional (3D) nanocolumn bundles-like morphology was obtained for WO3 center dot 0.33H(2)O and RGO-WO3 center dot 0.33H(2)O. Whereas with subsequent heat treatment at 400 degrees C, it was possible to obtain h-WO3 and RGO-h-WO3 composites while preserving the nanocolumn bundles-like morphology. The sensing properties of these materials were investigated by exposing them to various VOCs at room temperature and at 55% relative humidity. We found that all the materials behave as a p-type semiconductor after being exposed to reducing gases. Response to 100 ppm of acetone to the RGO-h-WO3 sensor was observed to be 20% larger than the h-WO3 sensor. (AU)

• FAPESP's process: 14/17343-0 - Effect of metal catalysts or reduced graphene oxide on metal oxides semiconductors for detection of volatile organic compounds
• Grantee: Diogo Paschoalini Volanti
• Support type: Regular Research Grants
• FAPESP's process: 15/05916-9 - Synergy between Pd-SnO2 or reduced graphene oxide-SnO2 for volatile organic compounds detection in humidity
• Grantee: Cecilia de Almeida Zito
• Support type: Scholarships in Brazil - Master
• FAPESP's process: 13/23886-4 - Study on selectivity of hydrogenolysis / reductive hydrogenation processes of sugarcane bagasse under supercritical state catalyzed by structured metal oxides
• Grantee: Mauricio Boscolo
• Support type: Program for Research on Bioenergy (BIOEN) - Regular Program Grants
• FAPESP's process: 15/04306-2 - One-pot microwave-assisted hydrothermal synthesis of tungsten trioxide-reduced graphene oxide composites for detection acetone
• Grantee: Tarcísio Micheli Perfecto
• Support type: Scholarships in Brazil - Scientific Initiation