The influence of charge compensation defects on the spectroscopic properties of europium doped Ca₉Y(PO₄)₇

Abstract

In this study, a series of Ca9Y(PO4)7 compounds doped with 5% of Eu ions and with different [Y]/[Ca] ratios was synthesized using the Pechini method.

Influence of Al3+co-doping on the spectral properties of europium doped Ca9Y(PO4)7

“…However, it was observed also in previous study for the samples aer reduction. 14 The obtained results show the Pechini method is very suitable to obtain well dened phosphors. The signal at 50.42 degree of 2q is attributed to the apparatus artefact.…”

“…The reduction of Eu 3+ occurs when the negative compensator of Eu Ca is locally neutralized. [12][13][14][15] The neutralization process can be attributed to the physical elimination of the compensator from the surroundings of Eu 3+ or to the emergence of another positively charged defect in the surroundings of the compensator. When the concentration of aluminum increases, the compensation of Eu 3+ via the Al 00 P becomes more probable, thus, naturally created compensators of europium, e.g.…”

“…The details of the synthesis procedure can be found elsewhere. 13,14,16 The water solution of the above mentioned reactants, weighted in appropriate molar ratio, was heat treated and then solvent was evaporated. The obtained dry polyester was calcined at 1250 C for 4 h in air.…”

“…The excitation light source was a xenon lamp 150 W emitting in the 220-800 nm range. 11,14 The experimental setup for luminescence kinetics and time resolved emission spectra consists of YAG:Nd laser of PL 2143 A/SS type and the parametric optical generator PG 401/SH (OPG). 17 The laser generated pulses of the 355 nm wavelength with frequency 10 Hz and pump PG generator which could produce light pulses with wavelength ranging from 220 nm to 2200 nm.…”

“…Here, it is expected that the incorporation of aluminum into the phosphate lattice will create negatively charged Al 00 P defect that is supposed to interact similarly as Ca 0 Y postulated in previous study. 14…”