Sankar, R. and Subbarao, G.V. (1998) Luminescence studies on doped borates, A6MM'(BO3)6. Journal of Alloys and Compounds, 281 (02). pp. 126-136. ISSN 0925-8388

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Abstract

Select compounds of the new hexaborates of the type A6MM'(BO3)6 have been synthesized by the solid state reaction and are subjected to photoluminescence studies after due characterization by powder XRD, density, TG/DTA, IR and Diffuse reflectance spectroscopy. The results of investigations on the photoluminescence of the compounds of the type, Sr6EuM'(BO3)6 with A=Sr; M=Eu; M'=Al, Ga, In; LaSr5MM'(BO3)6 : Eu with A=La, Sr; MM'=YMg, ScMg, MgAl; SmSr5YMg(BO3)6 , Sr6MAl(BO3)6 with M=Gd, Dy; Sr6YAl(BO3)6 : Bi, Pb; and La2Sr4SrMg(BO3)6 : Pb, are presented here. A new compound EuSr5YMg(BO3)6 has also been synthesized and studied. The luminescence features of Eu, Sm, Gd, Dy, Bi (all 3+) and Pb ions are discussed. Red emission by Eu3+ ion doped both at the A and M sites have been studied at low and high Eu concentrations and the data analysed with respect to the site occupancy and the possible site disorder. The positions of the emission lines depend not only on the site occupancy but also on the ions present at the M' site. The variation in Eu3+ emission intensity with its concentration reveals a near-saturation behaviour, as evidenced by studies on La1-xEuxSr5YMg(BO3)6 (x=0.05–1.0). The Pb2+ ion exhibits efficient violet luminescence under 254 nm excitation. The results establish that these hexaborate compounds are excellent hosts for the high efficiency room temperature luminescence of the lanthanide (Eu, Sm, Gd, Dy) and Bi, Pb ions.

Item Type:	Article
Uncontrolled Keywords:	Luminescence; Lanthanides; Hexaborates
Subjects:	Electrochemical Materials Science
Divisions:	UNSPECIFIED
Depositing User:	ttbdu cecri
Date Deposited:	04 May 2012 10:59
Last Modified:	04 May 2012 10:59
URI:	http://cecri.csircentral.net/id/eprint/1365

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