Efficient Light Harvesting within C153@Zr-Based MOF Embedded in a Polymeric Film: Spectral and Dynamical Characterization

M. Gutiérrez, M. López-González, F. Sánchez and A. Douhal.
Physical Chemistry Chemical Physics 2017, DOI: 10.1039/C7CP02094E

Light harvesting is a natural phenomenon that scientists try to mimic in artificial systems. Having this in mind, interests have been focused on using new smart-materials for photonics. Herein, we report on the photobehaviour of Zr-NDC MOF and its composite material, Coumarin153@Zr-NDC embedded within a polymeric membrane of poly[bisphenol A carbonate-co-4,4’-(3,3,5-trimethylcyclohexylidene)diphenol carbonate] (PC). For the mixed matrix membrane (MMM) containing Zr-NDC/PC, we observed interparticles excimer-like formation, taking place in times shorter than 15 ps and giving birth to a red-shifted broad emission band. The interparticle interactions are supported by the SEM images, as they reflect the contact between the MOF crystals. The C153@Zr-NDC/PC material presents an energy transfer (ET) process from the excited MOF to trapped C153 molecules in 820 ps, with a 35-nm red-shifted emission band relating to C153 in PC. The fluorescence quantum yield, results of this ET from the MOF, is enough high (25%) to explore the possibility to use this new composite material in a LED device. To elucidate the observed photobehavior, we compared with those of C153/PC and (2,6-NDC + C153)/PC films. These results shed light on the spectroscopic and dynamical properties of this new composite materials formed by a highly fluorescent molecule, and easy-synthesized MOF and polymeric matrixes, opening the way for more research based on these mixed inorganic and organic compounds for possible applications in luminescence sensing and emitting devices fields.