Luminescence tuning of the Dy–Zn metal–organic framework and its application in the detection of Fe(iii) ions. Issue 19 (13th April 2016)

• Record Type: Journal Article
• Authors: Li, Yu-Fei; Wang, Dan; Liao, Zhuang; Kang, Yang; Ding, Wei-Hua; Zheng, Xiang-Jun; Jin, Lin-Pei
• Is Part Of: Journal of materials chemistry. Volume 4:Issue 19(2016)
• Page Start: 4211
• Page End: 4217
• Publication Date: 2016-04-13
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6tc00832a
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : A single-component Dy–Zn MOF with white-light emission was used to detect Fe(iii ) with the combination of f–f transitions and ligand-based emission, which provides a platform for the design and application of the white-light emitting materials and chemosensors for metal ions. Abstract : A new Dy(iii )–Zn(ii ) heterometallic-organic framework [H(H2 O)8 ][DyZn4 (imdc)4 (im)4 ] (Dy–Zn MOF) (H3 imdc = 4, 5-imidazole dicarboxylic acid, im = imidazole) was synthesized under the hydrothermal conditions and characterized by single-crystal X-ray diffraction. The Dy–Zn MOF possesses the characteristic Dy(iii ) emission with a lifetime and a quantum yield of 54.65 μs and 5.5%, respectively, when excited at 290 nm. The luminescence of the Dy–Zn MOF can be tuned by the excitation wavelength to give white-light and yellow emissions based on emissions of Dy 3+ and the ligands imdc 3− and im. The energy transfer pathways at different excitation wavelengths were discussed. Furthermore, the Dy–Zn MOF can act as a turn-off chemosensor for Fe 3+ with high selectivity and sensitivity. The resultant species at different molar ratios of Dy–Zn MOF and Fe 3+ in the response system were obtained and have the general formula [H(H2 O)8 ][DyZn4− x Fe x (imdc)4 (im)4− x (OH) x ] with the same framework as the Dy–Zn MOF. The sensing mechanism could be described as the adsorption of Fe 3+ and displacement of Zn 2+ by paramagnetic Fe 3+ in the Dy–Zn MOF to form the Dy–Zn–Fe MOF, resulting in fluorescence quenching. The quenching constant was determined to be 9.29 × 10 5 M −1 .