Improved steady-state photoluminescence derived from the compensation of the charge-imbalance in Ca3Mg3(PO4)4:Eu3+ phosphor

Abstract This work focuses on the charge-compensation effects produced by different monovalent alkali ions, viz. Li+, Na+, K+, and the vacancy defects in the Eu3+-activated Ca3Mg3(PO4)4 host. To compensate the extra charge produced due to doping of Eu3+ ions in the Ca2+ site, two approaches were adopted. In the first approach, a Ca2+ vacancy (□+) was deliberately created in such a way that three Ca2+ ions were removed for doping of every two Eu3+ ions. In the second case, a monovalent alkali ion (Li+, Na+ or K+) was incorporated along with one Eu3+ ion to replace two Ca2+ sites in the host. Sol-gel/Pechini method was employed for the synthesis. The luminescence emissions of Ca3Mg3(PO4)4;Eu3+ phosphor significantly improved with the introduction of charge-compensators. The remarkable enhancement in the emission intensity of the charge-compensated samples was accompanied by noteworthy improvement in the color purity of their emissions.