Design, synthesis and characterization of sensors based on mesoporous thin films and nanometals

PAULA C. ANGELOMÉ

Bariloche

Workshop; What is bright with light?; 2016

Mesoporous oxides thin films (MPTF) have attracted increased interest in the last twenty years, mainly because of the wide variety of applications that can be envisioned for them. These materials are prepared combining the self-assembly of amphiphilic molecules (which act as templates) and sol-gel reactions (which give rise to the oxide). Thus, the oxides present an extremely high specific surface area and highly ordered arrays of monodisperse pores (diameters in the range 2-10 nm). This porosity can be exploited to filter molecules, incorporate functions or particles, condense vapors and catalyze reactions. These features of MPTF can be combined with the interesting optical properties of metallic nanoparticles or thin films, giving rise to nanocomposites with novel properties, which can be exploited to build devices. In this talk, some examples of sensors prepared from the combination of MPTF with nanometals will be described. First, a selective Surface Enhanced Raman Spectroscopy based sensors will be presented [1, 2]. In this case, the selectivity is achieved by controlling the porosity and the chemical composition of a MPTF deposited on top of a submonolayer of metallic nanoparticles. Next, an example of the combination of a metallic thin film with a porous 1D photonic crystals build from MPTF will be presented [3]. The composite material present a Tamm Plasmon, that can be exploited to detect the presence of organic vapors with a high sensitivity. Finally, new electrochemical and optical sensors based on composites that are currently under development will be introduced. In all examples, the attention will be focused on the sensors? rational design and its synthesis by chemical methods. [1] López-Puente, V.; Abalde-Cela, S.; Angelomé, P. C.; Alvarez-Puebla, R. A.; Liz-Marzán, L. M., J. Phys. Chem. Lett. 2013, 4, 2715-2720[2] López-Puente, V.; Angelomé, P. C.; Soler-Illia, G. J. A. A.; Liz-Marzán, L. M., ACS Appl. Mater. .Interf. 2015, 7, 25633-25640.[3] Auguié, B.; Fuertes, M. C.; Angelomé, P. C.; López Abdala, N.; Soler Illia, G. J. A. A.; Fainstein, A., ACS Photonics 2014, 1, 775-780.