Study On Synthesis And Photoluminescence Of RE/SBA-15

RE(Rare Earth) complexes have attracted considerable attention owing to their excellent optical properties, but they have been excluded from application as phosphors because of the poor thermal, photochemical and mechanical stability. One of the methods for applying these organic substances as optical elements in optoelectronic and photonic devices is to fix them in inorganic hosts so that optical and thermal functions might be stabilized. In this paper, SBA-15 mesoporous molecular sieve was chosen as a host for rare earth complexes incorporation. Study was done to investigate the performance of SBA-15 mesoporous material as a host for organic luminescent substances to solve the problems in the application of the latter and the influence on optical properties exerted by incorporation. Moreover, the work is to enrich and develop the principle of host-guest assembly chemistry.This paper consists of the content on following three aspects:1. The best synthesis condition of SBA-15 was given by study straightly alternate experiments, tetraethylortho silicate (TEOS) as the source of silica and Pluronic P123 as the template. It was shown that mesoporous silica SBA-15 had been synthesized in this work with uniformly sized pores and long-distance ordered arrangement of hexagonal structure.2. Tb(DBM)3phen and Eu(DBM)3phen were incorporated into the channels of mesoporous materials SBA-15 by the conjunction of silicane, in which —OH on the inner surface of mesoporous channels was taken place by active —NH₂. Result reflects the incorporation of the RE chelate decreased the order degree of mesoporous materials SBA-15, but composite materials remained hexagonal mesoporous structure. In PL spectra, the maximum excitation wavelength of the assembly shows blueshift compared to unassembly because of the different local environments coming from the —NH₂ groups in the channels of SBA-15 and nano effect. In addition, because the anchored amine of the APTES-SBA-15 has a great effect on the complex field, which surrounds the RE³⁺ ion due to thesymmetry of the complex sharp increase. Furthermore, the color purity of materials increases.3. (Y, Eu) (DBM)3phen/APTES-SBA-15, in which Eu3+ was partly taken place by low cost Y3+, was prepared and incorporated into mesoporous materials SBA-15 as guest materials. Result reflects the incorporation of the RE chelate decreased the order degree of mesoporous materials SBA-15. In PL spectra, the maximum excitation wavelength of the assembly shows blueshift compared to unassembly because of the different local environments coming from the —NH2 groups in the channels of SBA-15 and nano effect. Meanwhile, the color purity of materials increases and better photostability is also obtained by incorporation.