ABSTRACT
Several erbium organic complexes, hydrated erbium binary complexes with acetylacetone (AcAc) or dibenzoylmethane (DBM), erbium ternary complexes derived from 1,10-phenanthroline (Phen) with acetylacetone (AcAc), dibenzoylmethane (DBM) or trifluoroacetylacetone (TFA), were synthesized and identified by elemental analysis. The UV-Vis absorption and FTIR spectra measurements have been employed for all the erbium complexes. Near infrared (NIR) photoluminescence properties, such as luminescence intensity and effective bandwidth, of the erbium complexes were also studied. As a result, the erbium ternary complex with AcAc and Phen exhibits the most excellent luminescence properties among those investigated complexes.
Subject(s)
Erbium/chemistry , Luminescence , Organometallic Compounds/chemistry , Spectroscopy, Near-Infrared , Chalcones/chemistry , Luminescent Measurements/methods , Organometallic Compounds/chemical synthesis , Pentanones/chemistry , Phenanthrolines/chemistry , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform InfraredABSTRACT
Doping 2,2'-bipyridine molecules in silica gel glass leads to special spectroscopic properties compared to those dissolved in liquid solutions. For the sample without heat treatment, two broad bands centered at 400 nm and 454 nm respectively, induced by the radiative transition from the first excited level S1 to the ground level S0 and attributed to the emission from an excited dimeric 2,2'-bipyridine species respectively, were observed. After heat-treated at 200 degrees C, the excimer emission at 454 nm disappeared, and the sample exhibited another emission band centered at 325 nm due to the radiative transition from the second excited level S2 to the ground level. S2-->S0 transition resulted from restricting 2,2'-bipyridine molecules in silica networks. Only the structure emission of S2-->S0 transition was observed when heat-treated at 550 degrees C, which indicates that most of 2,2'-bipyridine molecules were entrapped in the cages of Si-O network. The above results can be used to characterize the microstructural evolution of hybrid organic-inorganic optical materials.
Subject(s)
2,2'-Dipyridyl/chemistry , Glass/chemistry , Phase Transition , Silicon Dioxide/chemistry , Gels/chemistry , Hot Temperature , Silica Gel , Spectrometry, Fluorescence , ThermodynamicsABSTRACT
We report here the preparation of nickel tetrasulfo-phthalocyanine (NiTSPc)-doped silica xerogel matrix obtained by sol-gel technique. The evolution of silica matrix's texture and the rate during the sol-gel process, as well as silica xerogel's pore structure were studied. Dimerization behavior of NiTSPc molecules was characterized by electronic absorption spectra, and changes in the absorption spectra were correlated with various stages of the sol-gel process. The results show that in the composites NiTSPc concurs in the forms of monomer and dimer, and dimerization is stronger during the latter stages. The reason is given from the change in the micro-environment in which NiTSPc existed during the sol-gel process.
