2(水杨醛缩苯胺)-(1,10-邻菲罗啉)合钙的光谱特性

Optical Spectroscopy of 2(salicylaldehyde with aniline)-(1,10-phenanthroline)calcium

合成了一种新型的蓝光发射材料2(水杨醛缩苯胺)-(1,10-邻菲罗啉)合钙,并利用红外光谱、X射线衍射谱、DSC热分析、UV-vis吸收谱、荧光激发光谱和荧光发射光谱研究了其结构、晶态、热稳定性以及光学特性,分析了它的能态结构和发光机理。结果表明,2(水杨醛缩苯胺)-(1,10-邻菲罗啉)合钙的热稳定性较高,是一种多晶粉末发光材料,禁带宽度2.93 eV,在紫外光的激发下,固态荧光发射峰在449.7 nm处,在乙醇溶液体系中的荧光发射峰在491 nm处,均为蓝色荧光,色纯度高,荧光量子效率高,其荧光发射主要来源于长波吸收带,最大波长吸收带对荧光发射贡献最大。

A new light emitting material, 2 （ salicylaldehyde with aniline） -（1,10-phenanthroline） calcium was synthesized. Its molecular structure, crystal structure, thermal stability and optical properties were investigated by FTIR spectra, XRD spectra, DSC thermal analysis, UV-vis spectra, fluorescence excitation spectrum and fluorescence spectrum, respectively. Its energy band and light emission mechanism were studied. Results show that 2 （salicylaldehyde with aniline） -（1,10-phenanthroline） calcium is a thermally stable, polycrystalline material, whose melting point is about 325 ℃. In its infrared spectrum, a high intensity band is at about 1 650 cm^- 1. This band is typical of the conjugated C =N stretching vibration, which shift to higher frequency in relation to the free ligand of salicylaldehyde with aniline. A very weak band at 1 248 cm^-1 is assigned to ph-O stretching vibration, which is weaker than that of the free ligand of salicylaldehyde with aniline. New band at 655 cm^-1 is assigned to Ca-O stretching vibration. Its ethanol solution can emits intense blue fluorescence with peak wavelength of 491 nm and its powder also emits intense blue fluorescence with peak wavelength of 449.7 nm under UV irradiation. The redshift of 41.3 nm of fluorescence peak wavelength of 2 （salicylaldehyde with aniline）-（1,10-phenanthroline） calcium in ethanol solution relative to its powder state is caused by solvent effect. Its UV absorption bands are at about 222,258,325 and 388 nm, respectively. The absorption bands at about 222 nm and 258 nm are attributed to intrinsic at about 325 nm and 388 nm are assigned to intrinsic absorp absorption of benzene ring. The absorption band tion of C =N. Its optical gap is about 2.93 eV, which was determined by intrinsic absorption band edge of 2 （salicylaldehyde with aniline）-（ 1,10-phenanthro- line） calcium in ethanol solution. Its fluorescence excitation spectrum has two excitation bands located at 361.5 nm and 409.5 nm, respectively. Its fluorescence originates chiefly from the long wavelength excitation band of 409.5 nm.