In situ synthesis, crystal structure and photophysical properties of a new binuclear europium compound

• Published in: Inorganica Chimica Acta 2023-08, Vol.553, p.121522, Article 121522
• Main Authors: Luo, Hui, Wei, Li-Jun, Xu, Yu-Yue, Yi, Xiu-Guang, Chen, Wen-Tong, Lin, Wei-Sheng
• Format: Article
• Language: English
• Subjects: Crystal; Europium; Hydrothermal; Lanthanide; Photoluminescence
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/j.ica.2023.121522

A novel europium complex was synthesized. It features a binuclear structure. A photoluminescence measurement with solid-state samples reveals that it can emit brown photoluminescence. It has CIE (Commission Internationale de I'Éclairage) chromaticity coordinates (0.557, 0.4292) and its CCT (Correlated Color Temperature) is 1871 K. The solid-state diffuse reflectance spectra reveals that it has a wide semiconducting bandgap of 4.09 eV. [Display omitted] •It reports a novel europium complex with a binuclear structure.•It displays brown photoluminescence.•It has CIE chromaticity coordinates (0.557, 0.4292) and its CCT is 1871 K.•The semiconductor bandgap is 4.09 eV. A new europium compound [Eu2(H2O)8(MBA−)4](2MBA−) (1; MBA− = methylsulfanyl-benzoic acid anion) was synthesized via an in situ reaction of EuCl3·6H2O, 4,4′,4″-(1,3,5-triazine-2,4,6-triyltrisulfanediyl)tribenzoic acid, methanol and distilled water under hydrothermal conditions. The crystal structure is characterized by single-crystal X-ray diffraction and features a binuclear structure. The molecules are interlinked via hydrogen-bonding interactions to form a one-dimensional (1-D) supramolecular chain. A photoluminescence measurement with solid-state samples reveals that compound 1 can emit brown upconversion photoluminescence with the maximum peak locating at 622 nm and a weaker one at 590 nm. The bands are ascribed to the characteristic emission of the 4f electron intrashell transition of the 5D0 → 7F1 and 5D0 → 7F2 of the Eu3+ ions. Compound 1 exhibits CIE chromaticity coordinates (0.557, 0.4292) and its CCT is 1871 K. The solid-state diffuse reflectance spectra reveals that compound 1 has a bandgap of 4.09 eV.