Photoluminescence of Eu3+-activated GdTaO4 with both M type and M' type structures

• Published in: Journal of materials science 2000-03, Vol.35 (5), p.1139-1143
• Main Authors: BO LI, ZHENNAN GU, JIANHUA LIN, SU, M.-Z
• Format: Article
• Language: English
• Subjects: Banded structure; Charge transfer; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Emission spectra; Energy transfer; Europium; Exact sciences and technology; Excitation spectra; Gadolinium; High temperature; Luminescence; Materials science; Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other solid inorganic materials; Photoluminescence; Physics
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1023/A:1004767916006

A series of Eu3+ doped M and M′ type gadolinium orthotantalate Gd1− xEuxTaO4 (x = 0–0.20) have been synthesized by high temperature solid state reaction. The emission and excitation spectra for M and M′ type gadolinium orthotantalate are studied in detail. The structural difference between M and M′ type structure obviously influences their luminescence properties. The main excitation bands in M′ type Gd1− xEuxTaO4 shift to shorter wavelength because of a shorter distance of Ta-O in comparison with M type. The strong evidence from excitation spectra, emission spectra and diffusive reflection spectra of these two system show Gd3+ can play an intermediate role of energy transfer in the process of luminescence. There is energy transfer from TaO43− to Gd3+ and finally to Eu3+ via the charge transfer states and spectral overlap.