Photoluminescence study in Ce3+ activated M6B5AlO15 (M = Sr, Ca, Ba) and mixed host aluminoborate phosphors

In this paper we report the modified solid state synthesis of Ce3+ activated Sr6B5AlO15, Ca6B5AlO15 Ba6B5AlO15 and mixed host aluminoborate phosphors. The prepared phosphors were characterized by photoluminescence technique. The PL excitation spectra showed the excitation peaks ranging from 300 to 400 nm and emission spectra are observed in UV-blue region of spectrum and it varied for different hosts. This kind of emission is due to 4f65d → 4f7 transition of Ce3+ ion. Further PLE and PL emission spectra for various compositions Ca5Sr1B5AlO15, Ca4Sr2B5AlO15, Ca3Sr3B5AlO15, Ca2Sr4B5AlO15, CaSr5B5AlO15 are also taken which shows Ce3+ emission at 428 nm, 425 nm, 432 nm, 427 nm, 438 nm respectively. The calculated 2FJ (J = 7/2, 5/2) energy gap of Ce3+ in all hosts have been calculated and obtained values for Sr6B5AlO15, Ba6B5AlO15 phosphors are 1888 cm−1 and 1330 cm−1 respectively. PL emission spectra of mixed host aluminoborates have shown slight variations in positions of emission peaks.