Photo-Responsive TiO2-Gold Nanoparticle-Polymer Nanohybrid Exhibits Photothermal, Thermo-Release, and Photocatalytic Effects

Abstract

The development of multi-responsive nanohybrid systems that combine photothermia, thermo-responsive effects and photocatalysis is a challenging topic in the research of multifunctional materials with a large field of applications. Here, we report the first example of a three-components light-responsive nanosystem consisting of titania, gold nanoparticles and poly-N-isopropylacrylamide (TiO₂-Au-PNM). The hybrid nanostructure exhibited photothermal conversion effect upon green-light excitation and capacity to entrap methylene blue and curcumin selected as cargo models. The formation of the nanohybrid–cargo adducts, the photothermal-controlled cargo release triggered by green-light irradiation (532 nm) and mediated by lower critical solution temperature (LCST), as well as the photocatalytic effect prompted by UV-light excitation (300 nm) were demonstrated by spectroscopic techniques. The mechanism involved in the interaction of the polymeric component with the cargos was investigated by molecular modelling calculations.