MESOPOROUS FILMS LUMINESCENT DOPED WITH [Eu(Tp)

Abstract

Purpose: The mesoporous materials have large specific area and pore volumes, low density, high mechanical and thermal stability, and can have a wide range of application as catalysis, shape-selective adsorbents, chemical sensors, capsules for controlled release of therapeutic agents, microelectronics, electro-optics, and other emerging nanotechnologies. The sol-gel process stands out for the advantages it presents as energy saving, low preparation temperature and formation of homogeneous products. Methods: Eu 3+ -complex containing tris-(pyrazolyl) borate called “scorpionate” (Tp) - [Eu(Tp)] - was incorporated via wet-impregnation into mesoporous silica films. The SG precursor solution was prepared by homogenization of tetraethylorthosilicate, deionized water, ethanol and cetyltrimethylammonium bromide. The films were obtained by the dip-coating technique with deposition rate of 300 mm/min, varying from 1 to 5 depositions, using borosilicate glasses as substrates. The films were characterized by X-ray diffraction and photoluminescence. Results: The results obtained showed a highly ordered hexagonal array of mesochannels. Luminescence results reveal bands corresponding to the intra-configurational transitions 5 D 0 a 7 F J (J = 0, 1, 2, 3 and 4) regardless the depositions number. Conclusion: The film presents intense red-emission at 613 nm, when excited in the ligand, the antenna effect was observed by ligand metal transfer energy. The photoluminescence properties showed that luminescence film can be used as sensors.