Antenna Effect in Highly Luminescent Eu³⁺ Anchored in Hexagonal Mesoporous Silica

A route for coordination of Eu 3+ by dibenzoylmethane (DBM) covalently bonded inside hexagonal mesoporous silica was established here to produce the highly luminescent nanomaterial SiDBM−Eu(DBM) 2 . Thermogravimetry, luminescence, X-ray diffraction, N 2 adsorption, FTIR, FTRaman, 29 Si NMR, and 13 C NMR in solid-state techniques were used to characterize SiDBM−Eu(DBM) 2 . The 29 Si NMR spectrum proved that the DBM was covalently bonded to a silica framework. Thermogravimetric and titration data showed the 6.4 × 10 - 2 mmol of Eu 3+ per gram of silica, and each Eu 3+ is coordinated by three DBMs in SiDBM−Eu(DBM) 2 . SEM images confirmed that this material is formed by nanoaggregates with 200 nm diameter. N 2 adsorption isotherms showed the SiDBM−Eu(DBM) 2 complex with 800 m 2 g -1 and 6.4 nm of porous diameter, characterizing mesoporosity of this nanomaterial. SiDBM−Eu(DBM) 2 showed an efficient DBM to Eu 3+ intramolecular energy process, namely, antenna effect, which favored a highly luminescent behavior in this modified hexagonal mesoporous silica.