Achieving high thermal stability of different rare-earth ions in a single matrix host via the manipulation of the local structure by a solid solution.

Thermal quenching seriously restricts the practical application of phosphors, particularly under high temperature and long-term working conditions. Here, we demonstrate that the as-obtained series of solid solutions of Ca2-xYxAl2Si1-xAlxO7:Tb3+ (x = 0-1, Ca2Al2SiO7 → CaYAl3O7) phosphors exhibit an adjustable optical performance, where CaYAl3O7:Tb3+ exhibits a greatly improved thermal stability with a shortened bond distance of the related polyhedron compared with Ca2Al2SiO7:Tb3+. The shrunken bond distance strengthens the pressure of the local structure and suppresses the non-radiative transition effectively, contributing to the prevention of the thermal degradation. The formed phosphor with excellent structural stability could be effectively incorporated with various lanthanide ions (Eu3+, Tb3+, Sm3+, Dy3+, and Pr3+) to address a pleochroism output.