红光拓宽型植物照明用荧光粉La_(2)MgTiO_(6)∶Pr^(3+),Mn^(4+)的合成和发光性质探究

Synthesis and Luminescence Properties of Broadened Red Light La_(2)MgTiO_(6)∶Pr^(3+),Mn^(4+)Phosphors for Plant Illumination

采用高温固相法合成了La_(2)MgTiO_(6)∶Mn^(4+)、La_(2)MgTiO_(6)∶Pr^(3+)、La_(2)MgTiO_(6)∶Pr^(3+),Mn^(4+)单掺杂和双掺杂荧光粉,并通过X射线衍射、扫描电镜、荧光光谱等测试方法对荧光粉的物相结构、形貌和发光特性进行了表征及分析。结果表明:成功合成了La_(2)MgTiO_(6)∶Mn^(4+)、La_(2)MgTiO_(6)∶Pr^(3+)、La_(2)MgTiO_(6)∶Pr^(3+),Mn^(4+)荧光粉且均为纯相;样品的粒径为1~2μm;La_(2)MgTiO_(6)∶Mn^(4+)在650~750 nm的红光发射是来自Mn^(4+)的2 E 1→4 A 2跃迁,La_(2)MgTiO_(6)∶Pr^(3+)在红光区域600~660 nm具有强烈的发射,归属为Pr^(3+)的3 P 0→3 H 6和3 P 0→3 F 2跃迁。当Mn^(4+)与Pr^(3+)共同掺杂于La_(2)MgTiO_(6)时,来自Mn^(4+)、Pr^(3+)不同波段的红光发射使荧光粉的发射光谱与植物光敏色素P r与P fr吸收光谱的重叠程度大幅增加,表明Mn^(4+)、Pr^(3+)共掺有效拓宽了La_(2)MgTiO_(6)荧光粉的红光发射区域,更符合植物照明的需求,在LED植物照明领域具有更明显的潜在应用价值。

La_(2)MgTiO_(6)∶Mn^(4+),La_(2)MgTiO_(6)∶Pr^(3+),La_(2)MgTiO_(6)∶Pr^(3+),Mn^(4+)single-doped and co-doped phosphors were synthesized by high-temperature solid-state method.The phase structure,morphology,and luminescence properties of the phosphors were characterized and analyzed by means of X-ray diffraction,scanning electron microscopy,and fluorescence spectrophotometer.The results show that,La_(2)MgTiO_(6)∶Mn^(4+),La_(2)MgTiO_(6)∶Pr^(3+),La_(2)MgTiO_(6)∶Pr^(3+),Mn^(4+)phosphors with pure phase were successfully synthesized.The particle size of the samples is 1~2μm.The red emission of La_(2)MgTiO_(6)∶Mn^(4+)at 650~750 nm is attributed to the 2 E g→4 A 2g transition of Mn^(4+).La_(2)MgTiO_(6)∶Pr^(3+)exhibits strong emission in the red light range between 600 nm and 660 nm,which is attributed to the 3 P 0→3 H 6 and 3 P 0→3 F 2 transition of Pr^(3+).Because of the different red light emission regions of Mn^(4+)and Pr^(3+),when they are co-doped in La_(2)MgTiO_(6),the emission spectra of the co-doped phosphors closely match with the absorption spectra of phytochromes P r and P fr.The results indicate that,compared to the single-doped phosphors,the red light emission region of the Mn^(4+),Pr^(3+)co-doped phosphors are widely extended.The red light emission region of the co-doped phosphors are more tally with the needs for plants grow.The La_(2)MgTiO_(6)∶Pr^(3+),Mn^(4+)phosphors has potential application in LED plant illumination.