Fine
control of nanoparticle clustering within polymeric matrices
can be tuned to enhance the physicochemical properties of the resulting
composites, which are governed by the interplay of nanoparticle surface
segregation and bulk clustering. To this aim, out-of-equilibrium strategies
can be leveraged to program the multiscale organization of such systems.
Here, we present experimental results indicating that bulk assembly
of highly photoactive clusters of titanium dioxide nanoparticles within
an in situ synthesized polysiloxane matrix can be thermally tuned.
Remarkably, the controlled nanoparticle clustering results in improved
degradation photocatalytic performances of the material under 1 sun
toward methylene blue. The resulting coatings, in particular the 35
wt % TiO2-loaded composites, show a photocatalytic degradation
of about 80%, which was comparable to the equivalent amount of bare
TiO2 and two-fold higher with respect to the corresponding
composites not subjected to thermal treatment. These findings highlight
the role of thermally induced bulk clustering in enhancing photoactive
nanoparticle/polymer composite properties.