Hydrosols of Titanium Dioxide Nanoparticles Containing Ti(IV) Peroxo Complexes: Modification, Optical Properties, Morphology, and Bleaching Kinetics

This paper reports the development and characterization of new inexpensive and safe light–time–temperature indicators for products of the pharmaceutical and food industries. For this purpose, we have prepared and characterized stable sols of titanium dioxide nanoparticles modified with titanium(IV) peroxo complexes. Electronic absorption spectroscopy, dynamic light scattering, scanning probe microscopy, and experimental kinetic data demonstrate that, varying synthesis conditions and, hence, the stability of the Ti(IV) peroxo complexes, one can ensure that their bleaching is symbatic with the degradation of a particular labeled object after the expiry date, and/or in the case of the required temperature conditions being not fulfilled, and/or during storage in the light. The most important result of this study is that we have found correlations between modification conditions of titanium peroxide sols, their optical properties, the morphology of films produced from them, and their bleaching kinetics under illumination.