Enhanced luminescence of Sr2SiO4:Dy3+ by sensitization (Ce3+/Bi3+) and its composition-induced phase transition

► Phase composition depends on the radius of doped ions and their concentrations. ► The doping with smaller ions is beneficial to obtain α′ phase. ► The codoping of Ce3+/Bi3+ enhances the luminescence of Dy3+ 3 or 2 times. ► Bright white light emission and stable CIE chromaticity coordinates. ► Energy transfer from donor to activator and electric multipoles interaction.