Hydrothermal Synthesis of Surface-Modified, Manganese-Doped TiO2 Nanoparticles for Photodegradation of Methylene Blue

Abstract

Abstract There has been a growing trend toward the addition of surface modifiers, surfactants, or capping agents to the precursors of titanium dioxide nanoparticles to tailor their morphology, structure, and size. In this study, surface-modified, manganese-doped titanium dioxide nanoparticles were successfully synthesized under mild hydrothermal conditions (pressure is autogenous; temperature, 250°C; time, 18 h). Using different molar ratios, we applied caprylic acid to change the surface chemistry and photocatalytic efficiency of manganese-doped titanium dioxide nanoparticles. Reagent grade titanium dioxide and manganese dioxide were the precursors, and concentrated hydrogen chloride was used as a solvent. Synthesized nanoparticles were characterized using powder x-ray diffraction, transmission electron microscopy, BET surface area, and ultraviolet-visible spectroscopy. Photodegradation studies of methylene blue were then carried out using ultraviolet and sunlight irradiation to compare the photocatalyti...