Physicochemical 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. The best photocatalytic degradation of methyl orange solution under UV light irradiation was recorded over MWCNTs-APTES-TiO2 (1:2), with 87% after 180 min. Kinetic analysis indicated that photocatalytic degradation of MO solution by MWCNTs-APTES-TiO2 obeyed second-order kinetic model (R2 > 0.95), supported by half-life equations and graph. The presence of carbon nanotubes accelerated the degradation of methyl orange due to inhibition of electron-hole 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 shows that the MWCNTs-APTES-TiO2 nanocomposites exhibit promising photocatalytic degradation against methyl orange.