Designed Mesoporous Nanoarchitectures as Platforms for confined Matter

G.J. A. A. SOLER ILLIA

Conferencia; XVI Brazilian MRS Meeting; 2017

The combination of sol?gel synthesis and surfactant self-assembly paved the wayto mesoporous materials with high surface area and controlled mesoporediameter (2-50 nm). Synthetic strategies to produce these systems evolved toachieve pore systems that can be ?decorated? with organic, biological ornanoscale functions. Control of pore size and geometry, wall composition andsurface features leads to tunable nanophase materials with prospectiveapplications in energy, catalysis, environment or nanomedicine.Although the focus has been set in exploiting the highly available surface areaand controlled pore diameter, several relevant aspects related to confinement arestill partially studied. These effects are important for several applications,because they imply the very behavior of matter within the mesopores. Examples of confinement effects in mesoporous materials will be presented.Confined water in mesoporous titania presents different water environments thatcan be distinguished and quantified by a combination of NMR and multi-scalemolecular dynamics simulations.1 The thermal evolution of gold nanoparticles(GNP) entrapped into mesoporous titania shows that particle coarsening starts attemperatures below 200 °C, assisted by the pore geometry.2 Transport of ions inperm-selective polyelectrolyte-loaded mesoporous silica thin films can be tuned bythe polymer charge or length, and interactions with the mesopore surface.3In all cases, a combination of careful synthesis procedures, in-situ characterizationtechniques and theory, in order to interpret the results, were employed. Theseexamples reinforce the concept that a concerted effort from different communitiesis needed to design novel nanosystems.