One-pot functionalization of carbon nanotubes by WO₃/MoO₃ nanoparticles as oxidative desulfurization catalysts

Abstract

Novel carbon nanotube hybrids with good catalytic properties can be obtained by a facile and fast method for immobilization of WO₃/MoO₃ on the surface and into the cavity of CNTs. We reported here a one-step wet chemical method for functionalization of MWNTs with tungsten and molybdenum oxides using oxodiperoxo complexes (WO₅/MoO₅) as precursors that can provide a novel methodology for future nanofabrication technology. The prepared WO₃/MoO₃-CNT hybrids were characterized by FTIR, XRD, SEM, TEM, and TGA analysis. It is suggested that the CNTs on treatment with WO₅ and MoO₅ complexes become functionalized and the end of the MWNTs was opened during the oxidation in the presence of peroxo groups. Then, WO₅/MoO₅ in the solution was adsorbed on the surface of CNT due to the coordination process. Finally, WO₃/MoO₃ nanoparticles are formed in-situ on the outer and inner surface of carbon nanotube during the treatment at 350 °C. WO₃/MoO₃ show a strong interaction with MWNTs and resulting WO₃/MoO₃-CNT hybrids were proven to be the good catalysts in oxidative desulfurization of the model fuel. The catalytic activity of the hybrid was found to increase when WO₃ react with functional group of CNTs. The best results (99.2%) have been obtained on the 2WO₃/MoO₃-CNT with the 16.5:8.5% wt. of WO₃:MoO₃.

Keywords:

• Tungsten oxide
• Molybdenum oxide
• Carbon nanotube
• Nanocatalyst
• Oxidative Desulfurization

Acknowledgment

Support of this investigation by chemistry and chemical engineering research center of iran is gratefully acknowledged.