Physiochemical properties of TiO2 nanoparticle loaded APTES-functionalized MWCNTs composites and their photocatalytic activity with kinetic study

In this study, functionalized-MWCNTs with 3-aminopropyltriethoxysilane (APTES) loaded titania nanoparticles (MWCNTs-APTES-TiO2) were prepared to investigate their physicochemical properties and photocatalytic activity for methyl orange (MO) degradation. The TiO2 nanoparticles, functionalized-MNCNT and composite powders were characterized by XRD, raman, and TEM. The results obtained proved that titania (TiO2) nanoparticles was successfully loaded on APTES-MWCNTs. For application, MWCNTs-APTES-TiO2 composites were used as photocatalyst for degradation of methyl orange (MO) in aqueous solution under UV light irradiation and the result shows that 87% MO was degraded after 180 min. Kinetic analysis indicated that photocatalytic degradation of MO solution by MWCNTs-APTES-TiO2 obeyed second-order kinetic model (R-2 > 0.95), supported by half-life equations and graph. Because of the presence of carbon nanotubes accelerated the degradation of methyl orange due to inhibition of electronhole recombination, the formation of additional hydroxyl radicals and functional groups of the latter had an inhibitory effect on the degradation of methyl orange. This study suggested the MWCNTs-APTES-TiO2 nanocomposite has considerable potential as environmental photocatalyst due to higher degradation rate as compared to bare TiO2. (C) 2018 Production and hosting by Elsevier B.V. on behalf of King Saud University.