Afterglow and mechanoluminescent properties of a novel cyan long-persistent luminescence phosphor Ba6BO3Cl9: Eu2+, Er3+

A new cyan long-persistent luminescence phosphor, Ba₆BO₃Cl₉: Eu²⁺, Er³⁺, was synthesized by high-temperature solid-state reaction. The thermoluminescence and afterglow properties of the phosphor were significantly improved by the co-doping of Er³⁺. The Ba₆BO₃Cl₉: Eu²⁺, Er³⁺ phosphor exhibited an emission peak in the range of 400–700 nm, centered at 472 nm under 355 nm excitation, which was attributed to the 4f⁶5d¹-4f⁷ transition of Eu²⁺. At the optimal doping concentration, the initial afterglow brightness of the Ba₆BO₃Cl₉: 0.1% Eu²⁺, 0.1% Er³⁺ sample reached 0.1 cd/m², and the afterglow lasted for more than 1.3 h. In addition, the synthesized Ba₆BO₃Cl₉: 0.1% Eu²⁺, 0.1% Er³⁺/polydimethylsiloxane composite elastomer exhibited a mechanoluminescent property.