Formation of Continuous Tungsten Oxide Coatings on Carbon Nanotubes Using Two Different Methods

Carbon nanotube/tungsten dioxide (CNT/WO2) hybrids were prepared by in-situ formation and coating of WO2 nanoparticles on CNTs using two alternative routes, both based on an aqueous solution processing technique and carried out at room temperature. In the first route, functionalized CNTs were used, whereas the other utilized pristine CNTs with benzyl alcohol as a surfactant to enhance the adhesion of nanoparticles. Microstructural and phase characterizations of the samples were carried out using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. For both types of CNTs, a 30% ethanol-70% water solution led to continuous coatings, however, weaker interaction between the CNTs and oxide particles was obtained when pristine CNTs were used for coating. Moreover, it was seen that the amount of ethanol in the solution had a crucial role on forming the coating when pristine CNTs were used.