Investigation of the mechanism responsible for the photoluminescence enhancement with Li+ co-doping in highly thermally stable white-emitting Sr8ZnSc(PO4)7:Dy3+ phosphor

The mechanism of the luminescence enhancement is consider as that a little amount introduction of Li+ ion can produce defects LiZn′ and oxygen vacancies VO¨, and with the incorporation amount of Li+ increasing, the more deep VO¨ are produced. As sensitizer, the productive deeper VO¨ can effectively tunneling transfer energy to nearby activator Dy3+ inducing its photoluminescence enhancement.151