This paper reports on the preparation, characterization, and photoluminescence properties of novel hybrid materials, in which the EDTA-Ln-L complexes (where L: H2 O, acac, bzac, dbm, and tta ligands, and Ln: Eu, Gd, and Tb) were covalently linked to the precursor medium molecular weight chitosan surface (CS) matrices or on the chitosan surfaces previously crosslinked with epichlorohydrin (CSech). The emission spectra of these materials were characterized by intraconfigurational-4fN transitions centred on the Eu3+ and Tb3+ ions. Some broad bands from the polymeric matrix were also observed in the emission spectra, however the relative intensities of the intraconfigurational bands increased significantly for systems containing diketonate ligands when the antenna effect became more efficient. The values of the radiative rates (Arad ) were higher for crosslinked hybrid systems with epichlorohydrin, while nonradiative rates (Anrad ) presented the opposite behaviour. These data contributed to an increase in the values of emission quantum efficiency (η) for crosslinked materials. The effect of the modification process and antenna ligand on the values of intensities, intensity parameters Ω2 e Ω4 of the Eu3+ complexes were also investigated. The results showed that the crosslinked biopolymer surfaces have great potential for applications in molecular devices light converters.

中文翻译：

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Ln-EDTA复合物的发光特性与包含β-二酮酸酯作为天线配体的壳聚糖生物聚合物共价连接。

本文报道了新型杂化材料的制备，表征和光致发光特性，其中EDTA-Ln-L络合物（其中L：H2 O，acac，bzac，dbm和tta配体，Ln：Eu，Gd， Tb和Tb）共价连接到前体中等分子量的壳聚糖表面（CS）基质上或预先与表氯醇（CSech）交联的壳聚糖表面上。这些材料的发射光谱通过以Eu3 +和Tb3 +离子为中心的配置内4fN跃迁进行表征。在发射光谱中也观察到了来自聚合物基质的一些宽带，但是当天线效应变得更有效时，对于含二酮酸酯配体的系统，构内带的相对强度显着增加。具有环氧氯丙烷的交联杂化体系的辐射率（Arad）值较高，而非辐射率（Anrad）则表现出相反的行为。这些数据有助于提高交联材料的发射量子效率（η）值。还研究了修饰过程和天线配体对Eu3 +配合物的强度，强度参数Ω2eΩ4值的影响。结果表明，交联的生物聚合物表面在分子器件光转换器中具有广阔的应用前景。还研究了修饰过程和天线配体对Eu3 +配合物的强度，强度参数Ω2eΩ4值的影响。结果表明，交联的生物聚合物表面在分子器件光转换器中具有广阔的应用前景。还研究了修饰过程和天线配体对Eu3 +配合物的强度，强度参数Ω2eΩ4值的影响。结果表明，交联的生物聚合物表面在分子器件光转换器中具有广阔的应用前景。