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Ultraviolet-emitting phosphors with the formula K2–xPbxAl2B2O7 (0.0025 ≤ x ≤ 0.03) were synthesized at 850°C for 6 h in air. The powder X-ray diffraction technique was used to analyze the phases of all prepared borates. The FTIR technique was used to examine the bond structure of K2Al2B2O7. At room temperature, a spectrofluorometer was used to examine the photoluminescence characteristics of the prepared phosphors. K2Al2B2O7:Pb2+ was found to have emission and excitation bands at 373 and 271 nm, respectively. An extensive investigation was conducted on the correlation between emission intensity and Pb2+ content for K2–xPbxAl2B2O7. Consequently, 0.01 mol Pb2+ was found to be the optimal concentration in K2Al2B2O7. Eventually, it was found that the Stokes shift of the prepared material K2Al2B2O7:Pb2+ is 10,090 cm−1 using the excitation band at 271 nm and the emission band at 373 nm. As a result of this investigation, a brand-new UVA radiation-emitting material has been established. [ABSTRACT FROM AUTHOR]

Abstract: Pure and Pb2+ doped M2Mg(BO3)2 (M=Sr, Ba) materials were synthesized at 900°C for 12h 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 Sr2Mg(BO3)2: Pb2+ were observed at 330 and 260nm, respectively. And, the emission and excitation bands of Ba2Mg(BO3)2: Pb2+ were observed at 381 and 293nm, respectively. The dependence of the emission intensity on the Pb2+ concentration for the M2−x Pb x Mg(BO3)2 (M=Sr, Ba) was studied in detail. It was observed that the optimum concentrations of Pb2+ in Sr2Mg(BO3)2 and Ba2Mg(BO3)2 are 0.06 and 0.01mol, respectively. The Stokes shifts of Sr2Mg(BO3)2: Pb2+ and Ba2Mg(BO3)2: Pb2+ phosphors were calculated to be 8159 and 7883cm–1, respectively. The luminescence behavior of the Pb2+ ion in M2Mg(BO3)2 (M=Sr, Ba) is discussed. [Copyright &y& Elsevier]

Abstract: Li6CaB3O8.5: M3+ (M3+: Dy and Sm) phosphors were synthesized by a solution combustion synthesis. The synthesized materials were characterized by using the powder XRD. The emission and excitation spectra of these materials were measured at room temperature with a spectrofluorometer. Both Li6CaB3O8.5: Dy3+ and Li6CaB3O8.5: Sm3+ phosphors emit red, yellow and green light. Consequently, these materials are promising phosphors for white LEDs. [Copyright &y& Elsevier]

Abstract: Pure, Pb2+ and Bi3+ doped LiCaBO3 materials were prepared by a solution combustion synthesis method. The phase of LiCaBO3 were determined using the powder XRD and FTIR. The photoluminescent properties of Pb2+ and Bi3+ doped LiCaBO3 materials were investigated using spectrofluorometer at room temperature. The emission bands of LiCaBO3: Pb2+ and LiCaBO3: Bi3+ were observed at 296 and 378nm, respectively. LiCaBO3 with different Pb2+ and Bi3+ doping concentrations were analyzed at room temperature. The Stokes shifts of LiCaBO3: Pb2+ and LiCaBO3: Bi3+ were calculated to be 3952 and 6440cm−1, respectively. [Copyright &y& Elsevier]

Abstract: Pure and Pb2+ doped LiSr4(BO3)3 materials were prepared by a solution combustion synthesis method. The phase analysis of all synthesized materials were determined using the powder XRD. The synthesized materials were investigated using spectrofluorometer at room temperature. The excitation and emission bands of LiSr4(BO3)3: Pb2+ were observed at 284 and 328nm, respectively. The dependence of the emission intensity on the Pb2+ concentration for the LiSr4(BO3)3 were studied in detail. It was observed that the concentration quenching of Pb2+ in LiSr4(BO3)3 is 0.005mol. The Stokes shifts of LiSr4(BO3)3: Pb2+ phosphor was calculated to be 4723cm–1. [Copyright &y& Elsevier]