Enhanced photoredox chemistry in surface-modified Mg2TiO4 nano-powders with bidentate benzene derivatives

Abstract

Magnesium-orthotitanate (Mg₂TiO₄) nano-powder was synthesized using a Pechini-type polymerized complex route. Microstructural characterization involving transmission electron microscopy, X-ray diffraction analysis and nitrogen adsorption–desorption isotherms indicated that well-crystallized Mg₂TiO₄ nanoparticles are small in size (about 10 nm) with large specific surface area (72 m² g⁻¹). The surface modification of Mg₂TiO₄ nano-powders with 5-amino salicylic acid and catechol induced a significant shift of absorption to the visible spectral region due to charge transfer complex formation. It should be emphasized that tunable optical properties of Mg₂TiO₄ nano-powders have never been reported in the literature. Degradation reactions of an organic dye (crystal violet) were used to test the photocatalytic ability of pristine and surface-modified Mg₂TiO₄ nano-powders under illumination in different spectral regions. Excitation with UV light indicated, for the first time, photocatalytic ability of Mg₂TiO₄. Also, improved photocatalytic performance of surface-modified Mg₂TiO₄ nano-powders was found in comparison to unmodified ones.