Sm^(3+)掺杂LaOF荧光粉的制备及光学性能

Synthesis and Luminescence Properties of Sm^(3+)Doped LaOF Phosphors

以LaOF晶体为基质,利用水热辅助固相法制备出一系列Sm^(3+)掺杂LaOF荧光粉。采用XRD、TEM、荧光光谱仪等测试手段对所制得的样品的相结构、微观形貌及光学性能进行表征。结果表明,LaOF在不同煅烧温度下会产生四方相和斜方六面体两种不同晶相。此外,由于受跃迁概率和局域对称性的影响,Sm^(3+)掺杂四方相LaOF发光强度更大,其各浓度样品在405 nm光激发下,于567 nm、605 nm、651 nm和710 nm等处均出现了Sm^(3+)的特征发射峰,并且随着Sm^(3+)掺杂量的增加,其发光强度呈现先增大后减小的趋势,且当Sm^(3+)掺杂量为3.0%(摩尔分数,下同)时,La_(1-x)Sm_(x)OF样品发光强度达最大值。此外,所得样品的色纯度极高,其多个激发峰均位于商用近紫外和蓝光LED芯片的发射波长附近,可实现多种波长激发下的可见橙光发射。

Aseries of Sm^(3+)doped LaOF phosphors were prepared by hydrothermal assisted solid-state method using LaOF crystal as matrix.The phase structure,microstructure and optical properties of the prepared samples were characterized by XRD,TEM and fluorescence spectrometer.The results show that at different calcination temperatures,two different crystalline phases,tetragonal and rhombohedral,are produced.Moreover,due to the transition odds and local symmetry,the Sm^(3+)doped tetragonal phase LaOF has a greater luminous intensity,and the characteristic emission peaks of Sm^(3+)appear at 567 nm,605 nm,651 nm and 710 nm under 405 nm excitation.With the increase of Sm^(3+)doping amount,the emission intensity of Sm^(3+)first increases and then decreases.When the doping amount of Sm^(3+)is 3.0mol%,the luminescence intensity of La_(1-x)Sm_(x)OF samples reaches the maximum.In addition,the excitation purity of the obtained samples is extremely high,and many excitation peaks of the samples are located near the emission wavelength of commercial near ultraviolet and blue LED chips,which can achieve visible orange light emission under excitation of various wavelengths.