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Pure and Pb 2+ doped M 2 Mg(BO 3 ) 2 (M=Sr, Ba) materials were synthesized at 900 °C for 12 h in air. The phases of the synthesized materials were determined using the powder XRD. The photoluminescence properties of the synthesized phosphors were investigated using a spectrofluorometer at room temperature. The emission and excitation bands of Sr 2 Mg(BO 3 ) 2 : Pb 2+ were observed at 330 and 260 nm, respectively. And, the emission and excitation bands of Ba 2 Mg(BO 3 ) 2 : Pb 2+ were observed at 381 and 293 nm, respectively. The dependence of the emission intensity on the Pb 2+ concentration for the M 2− x Pb x Mg(BO 3 ) 2 (M=Sr, Ba) was studied in detail. It was observed that the optimum concentrations of Pb 2+ in Sr 2 Mg(BO 3 ) 2 and Ba 2 Mg(BO 3 ) 2 are 0.06 and 0.01 mol, respectively. The Stokes shifts of Sr 2 Mg(BO 3 ) 2 : Pb 2+ and Ba 2 Mg(BO 3 ) 2 : Pb 2+ phosphors were calculated to be 8159 and 7883 cm –1 , respectively. The luminescence behavior of the Pb 2+ ion in M 2 Mg(BO 3 ) 2 (M=Sr, Ba) is discussed. |
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