Improvement of photoluminescence properties of Ce3+- doped CaSrAl2SiO7 phosphors by charge compensation with Li+ and Na+

摘要

In this work, we prepared CaSr(1-)xAl(2)SiO(7):xCe(3+) (0.03 = x = 0.12) and CaSr0.94Al2SiO7:0.03Ce(3+),0.03 M+ (M+ = Li+ and Na+) phosphors via solid-state reaction method. Structural and photoluminescence (PL) properties of the phosphors were also investigated. The prepared phosphors formed an orthorhombic crystal structure with the P2(1)2(1)2(1) space group. CaSr1-xAl2SiO7:xCe(3+) phosphors were effectively excited by near-ultraviolet (UV) light (345 nm), which is suitable with the emission of near-UV light emitting diode chips. A broad blue emission (402 nm) was detected in CaSri(1-x)Al(2)SiO(7):xCe(3+) and CaSr0.94Al2SiO7:0.03Ce(3+),0.03 M+ phosphors; this was attributed to the 4f(0)5d(1) - 4f(1) transition of Ce3+. To maintain charge equilibrium, charge compensators, such as monovalent Li+ and Na+ ions, were doped into the CaSr0.97Al2SiO7:0.03Ce(3+) phosphor, significantly improving its PL properties. The strongest emission intensity was achieved in CaSr0.94Al2SiO7:0.03Ce(3+,) ,0.03Li(+) phosphor. Addition of Li+ charge compensator was highly effective in improving PL properties of CaSr0.97Al2SiO7:0.03Ce(3+) phosphors.