2-(4-氯代苯甲酰基)苯甲酸配合物光致发光研究

Study on Photoluminescence of 2-(4-Chloro-Benzoyl) Benzoic Acid Complexes

以Eu3+,Tb3+为中心离子,2-(4-氯代苯甲酰基)苯甲酸(HCBBA)为第一配体,邻菲咯啉(Phen)、三苯基氧膦(TPPO)、二苯亚砜(DPSO)为第二配体,合成了多种铕铽的二元和三元配合物,并测试其荧光效能,以研究配体的加入对中心离子发光强度的影响。结果表明,合成的配合物均发出Eu(Ⅲ)和Tb(Ⅲ)的特征荧光,但相对强度明显不同。在铕与2-(4-氯代苯甲酰基)苯甲酸根(CBBA)形成的配合物体系中,Phen和DPSO显示了较强的敏化作用,且Phen敏化效果更强,而TPPO则对配合物荧光有猝灭作用。在Tb-CB-BA体系中,DPSO表现出很强的敏化作用,Phen和TPPO却对配合物荧光起猝灭作用,且TPPO猝灭效果更强。经红外推测,羧酸根均以双齿桥式与Eu3+和Tb3+配位;在3200～3600cm-1出现水的弱的羟基的伸缩振动吸收峰,表明配合物中含有结晶水。

Eight complexes of europium and terbium were synthesized,with 2-（4-chloro-benzoyl）benzoic acid as an essential ligand and other three distinct ligands,including 1,10-phenanthroline,triphenylphosphine oxide and diphenyl sulfoxide,as selective ligands. They were Eu（CBBA）3（H2O）4,Eu（CBBA）3（Phen）（H2O）6,Eu（CBBA）3（TPPO）（H2O）4,Eu（CBBA）3（DPSO）（H2O）5,Tb（CBBA）3（H2O）4,Tb（CBBA）3（Phen）（H2O）3,Tb（CBBA）3（TPPO）（H2O）2 and Tb（CBBA）3（DPSO）（H2O）4,respectively. Then their excitation and emission spectra were measured,and that how the central ions were differently impacted by the three second ligands was also compared. It was easily to be seen that from the spectra all the complexes luminesced with the similar special peaks. However,the luminescence intensity was evidently distinct,because 1,10-phenanthroline,triphenylphosphine oxide and diphenyl sulfoxide were coordinated with them,and exerted different effects on transferring energy to the central ions. In the complexes of europium,Eu（CBBA）3（Phen）（H2O）6 and Eu（CBBA）3（DPSO）（H2O）5 each luminesced more strongly than Eu（CBBA）3（H2O）4,however,Eu（CBBA）3（TPPO）（H2O）4 luminesced more weakly than Eu（CBBA）3（H2O）4. Moreover,Eu（CBBA）3（DPSO）（H2O）5 luminesced more intensely than Eu（CBBA）3（Phen）（H2O）6. So 1,10-phenanthroline and diphenyl sulfoxide could sensitize the luminescence,whereas triphenylphosphine oxide could quench the luminescence in the certain Eu complexes. In Tb complexes,diphenyl sulfoxide sensitized the luminescence of Tb（CBBA）3（DPSO）（H2O）4,and reversely,1,10-phenanthroline and triphenylphosphine oxide quenched differently the luminescence of Tb（CBBA）3（Phen）（H2O）3 and Tb（CBBA）3（TPPO）（H2O）2. 1,10-phenanthroline quenched more strongly than triphenylphosphine. From IR spectra,the structure of the complexes was conjectured approximately. In the region of 3 200-3 600 cm^-1,there were some weak vibrant peaks owed to hydroxyl of water,a good proof that there were water molecules in the complexes themselves.