“…Therefore, these materials, also known as long-lasting afterglow materials, are used for emergency displays, decorative purposes, background lighting, traffic signs, and escape route indicators. Recent studies have brought out many such phosphors like Eu 2+ , Dy 3+ -doped alkaline earth aluminates [1][2][3], Tb 3+ , Ce 3+ -doped alkaline earth aluminates [4], Eu 2+ , Dy 3+ and Eu 2+ , Ce 3+ -doped alumino silicates [5][6][7][8], Dy 3+ -doped strontium silicate [9], Eu 2+ , Pr 3+ -doped calcium sulfide [10], Pr 3+ , Li + -doped calcium zirconate [11], etc. However, among all these phosphors the Eu 2+ , Dy 3+ -doped alkaline earth aluminates are the most suitable phosphors due to their long persistence time and bright afterglow.…”