The photocatalytic degradation of methylen e blue on the surface of sol-g el p repared n anostructured ZnT iO۳ and Zn۲TiO۴

Semiconductor rese arch has been promisi ng in areas such as dy e-sensitized solar cells and photocatalytic remed iation of ha rmful orga nics from air and water. Among th e semicondu ctors investigated, titaniu m dioxide (TiO۲) has r eceived attention. On the other hand, zinc oxide (ZnO) h as also been promising in the areas of solar ce lls, gas sensors and photocatalysis. The simultaneous synthesis of a ZnO-TiO۲ comp osite usually results in the formation of one or more of the three known c ompounds from the ZnO-TiO۲ system: Zn۲TiO ۴ (zinc orthotitanate), w ith a cubic sp inel crystal structure; Zn۲Ti۳O۸, with a cubic defect spinel structure; a nd ZnTiO۳ (zinc metatitan ate), with a rhombohedral ilmen ite structure. Zn۲Ti۳O۸ is the metastableform of ZnTiO۳. Pure ZnTiO۳ is not e asily obtai ned, as it transforms to Zn۲TiO۴ and rutile. Zinc orthotita nate (Zn۲TiO۴) is an inverse spinel [۱, ۲]. These materials can be used for the photocatalytic compounds, but have a wide band gap (۳.۱ eV), restricting the ir photocatalyticactivity to ultraviol et (UV) lig ht [۳]. In th is study, w e prepared nanostructu red ZnTiO ۳ and Zn۲TiO۴ via a mod ified sol-g el method which has been devel oped in our laboratory and investigated the kinetics of photo catalytic degradation of methylene blue on their surfaces.

کلیدواژه ها:

Nanostructure ، ZnTiO۳ ، Zn۲TiO۴ ، photocatalyst