Rare earth activated luminescent material

In conclusion, well established luminescence spectroscopy techniques have been presented as a powefull tool to investigate sol-gel glasses. The present survey has been mainly devoted to rare earth-activated sol-gel materials, taking in account several technological applications which constantly push forward the research in this field. 

Luminescent solid-state materials comprised of insulating host lattices (normally oxides, fluorides, nitrides, and oxy-nitrides) activated by rare-earth and transition-metal ions continue to be an active area of research due to their application as phosphors, scintillators, and functional materials. 

As a famous and typical host emission or self-activated phosphor, Sr2Ce04 is novel blue luminescent material that has attracted much attention because it possesses some desirable qualities such as (i) ligands-to-metal charge transfer (CT) transition of Ce" " at approximately 340 nm, (ii) efficient energy transfer that can occur from the CT state to the trivalent rare-earth in Sr2Ce04 RE, ... 

The main focus of research on the rare earth silicates has been their preparation and structure. A summary of the structural data available is presented in table 14. In many cases the physical properties are unknown. An important application of the rare earth silicates is the use of yttrium oxyorthosilicate activated with terbium as a luminescent material in fluorescent lamps. Several patents have been published in this field. 

The rare earth phosphates activated with trivalent lanthanides can be used as luminescent materials and neodymium-containing polyphosphates reportedly make efficient laser materials (Palilla and Tomkus, 1969 Albrand et al., 1974 Koizumi, 1976b). 

A. J.W. O Laughlin, Chemical spectrophotometric and polarographic methods 341 37B. S.R. Taylor, Trace element analysis of rare earth elements by spark source mass spectrometry 359 37C. R.J. Conzemius, Analysis of rare earth matrices by spark source mass spectrometry 377 37D. E.L. DeKalb and V.A. Fassel, Optical atomic emission and absorption methods 405 A.P. D Silva and V.A. Fassel, X-ray excited optical luminescence of the rare earths 441 W.V. Boynton, Neutron activation analysis 457 37G. S. Schuhmann and J.A. Philpotts, Mass-spectrometric stable-isotope dilution analysis for lanthanides in geochemical materials 471... 

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