Yin-Xia Sun,Geng Guo,Wen-Min Ding,Wen-Yu Han,Juan Li,Zhe-Peng Deng
Heavy metal ions are common pollutants in water pollution. Amino acids, as important substances in organisms, participate in many life activities. The detection of heavy metal ions and amino acids with high selectivity and sensitivity is important. Therefore, based on H3L (H3L = 4,4′,4′′-triazine-2,4,6-tribenzoic acid) and Eu3+, an Eu-MOF was designed, synthesized and characterized. Single crystal structure analysis showed that the Eu-MOF was crystallized in the orthorhombic space group Fddd, and presents a three-dimensional (3D) porous network structure. The luminescence results show that the Eu-MOF has good luminescence stability. As a multifunctional luminescent sensor, the Eu-MOF can detect Fe3+, Cr2O72−, CrO42− and aspartic acid (Asp) in water systems with high sensitivity and selectivity, and the lowest detection limit (LOD) was 1.12 × 10−6 mol L−1, 1.95 × 10−6 mol L−1, 1.89 × 10−6 mol L−1 and 2.20 × 10−6 mol L−1, respectively. These results indicated that the Eu-MOF has potential application prospects in the detection of Fe3+, Cr2O72−, CrO42− and Asp in water.
Yanqiu Zhang,Jiaxiang Liu,Xiaohan Wu,Wenquan Tao,Zhuo Li
Accurate, simple and quick detection methods for Cr(VI) detection are urgently needed for water quality monitoring. Herein, a novel and facile method of detecting Cr(VI) (Cr 2 O 7 2− /CrO 4 2− ) ions is developed via the fluorescent detection technology based on metal-organic frameworks (MOFs) doped with sulfur quantum dots (SQDs) (SQDs@UiO-66-NH 2 ). The blue-light-emitting SQDs@UiO-66-NH 2 composites exhibit excellent fluorescent properties in water environment with high quantum yield (68%) and ideal fluorescent stability, thus demonstrating excellent potential for serving as a chemical sensor. After characterizing the performance and stability of SQDs@UiO-66-NH 2 , qualitative and quantitative detection of Cr 2 O 7 2− and CrO 4 2− ions was successfully conducted. The fluorescence of SQDs@UiO-66-NH 2 composites in aqueous solution was quenched effectively with more than 90% quenching efficiency by Cr(VI) via the inner filter effect. The detection system provides considerable advantages such as rapid response (10 s), high sensitivity with a low detection limit of 0.16 μM in a broad linear range of 0–200 μM (R 2 = 0.99) for Cr 2 O 7 2− and 0.17 μM for CrO 4 2− in a broad linear range of 0–220 μM (R 2 = 0.99), high selectivity and reproducibility for at least five cycles with simple washing with alcohol. In practical applications, the sensor showed rapid response, high sensitivity and excellent recoveries (96.7%–105.4%) for detecting Cr 2 O 7 2− in real water samples. Furthermore, a SQDs@UiO-66-NH 2 -based fluorescent test paper was successfully developed, providing a simple, reliable and portable method for Cr(VI) (Cr 2 O 7 2− /CrO 4 2− ) detection in water environment.
危险品化学品经营许可证（带存储）