Positron annihilation studies of Eu and Dy doped α'-Sr2SiO4

[摘要] Sr.2SiO4is an important inorganic host for lanthanide doped white light emitting diodes (LEDs). Strontium silicate (Sr.2SiO4) samples doped with 1.0 mol% of Eu3+and Dy3+content were prepared via sol-gel route and characterized by X-ray diffraction (XRD), Raman spectroscopy and positron annihilation spectroscopy (PAS). The concentration of the dopant ion and the temperature of annealing were optimized for maximum luminescence intensity. The positron annihilation lifetime and coincidence Doppler broadening (CDB) measurements indicated that the local environment around the positron annihilation site is different in Eu+3doped and Dy+3doped samples. The results could be explained based on the different local site occupancy of Eu+3and Dy+3in the matrix.

[发布机构] Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai; 400085, India^1

[效力级别] 化学

[关键词] Coincidence doppler broadening;Local environments;Luminescence intensity;Positron annihilation lifetimes;Positron annihilation spectroscopy (PAS);Sol-gel routes;Strontium silicate;White light emitting diodes