Surface modification of titanium oxide nanocrystals with PEG

In this study, surface modification of titanium oxide nanocrystals has been considered. PEG was employed to make bio-conjugated TiO2 nanopowders (TNPs). On the basis of the modification process, the effect of PEG on the size and morphology of prepared samples has been evaluated. It was found that the addition stage of PEG plays a critical role in the characteristics of TiO2 nanopowders. It was shown that PEG affects sol–gel reactions and the crystallization process of the prepared titanium oxide nanoparticles. PEG must be added before starting the synthesis to get well-defined size distribution, compared to post-synthesis. However, TiO2/PEG nanoparticles synthesized by the second approach have good photocatalytic performance, and the photodecomposition test of methylene blue proves that the addition of PEG after the synthesis of TiO2 improves the photocatalytic properties of prepared TiO2 nanoparticles. This phenomenon will affect TiO2 functionality, as well.