用于痕量监测Zr4+、Cr2O72-、Fe3+、HPO42-和指纹识别的功能化Eu3+/Tb3+配位聚合物荧光探针的构筑

采用芳香族π共轭及含氮原子有机连接剂，合成同构铽、铕发光配位聚合物(CPs){[Eu (PLIA)_1.5(H₂O)₂]·H₂O}_n (1)和{[Tb (PLIA)_1.5(H₂O)₂]·H₂O}_n (2)，其中H₂PLIA=5-((吡啶-4-基甲基)氧基)苯-1，3-二甲酸。对合成的配合物进行了结构测定、表征和荧光痕量识别实验研究。2个同构配合物具有理想的三维框架结构，π…π堆积及氢键等弱相互作用增强了其化学稳定性；表征显示配位聚合物1和2具有良好的荧光性质、结晶性、热力学稳定性及结构完整性，可作为荧光传感的材料。1和2对水溶液中的Zr⁴⁺、Cr₂O₇^2-和Fe³⁺、HPO₄^2-具有选择性好、灵敏度高的荧光识别能力，其检出限分别为0.139 μmol·L^-1(1，Zr⁴⁺)、0.626 μmol·L^-1(1，Cr₂O₇^2-)、0.430 μmol·L^-1(2，Fe³⁺)、1.36 μmol·L^-1(2，HPO₄^2-)。探究了1和2作为探针的荧光猝灭机理。更有趣的是，1和2具有指纹识别性能，其荧光指纹纹路清晰连贯，细节明显，可被清晰观察。

Design and synthesis of Eu3+/Tb3+-functionalized coordination polymers as visible fluorescent probes for trace monitoring Zr4+, Fe3+, Cr2O72-, HPO42- and identifying fingerprints

The isomorphic terbium and europium coordination polymers (CPs) {[Eu(PLIA)_1.5(H₂O)₂] ·H₂O}_n (1) and {[Tb(PLIA)_1.5(H₂O)₂]·H₂O}_n (2), where H₂PLIA=5-((pyridin-4-yl-methyl)oxy)benzene-1,3-dicarboxylic acid, were synthesized by using aromatic π-conjugated and nitrogen-containing organic linkers. The structure determination, characterization, and fluorescence trace identification of the CPs were studied. The two isomorphic complexes have an ideal 3D frame structure and their chemical stability is enhanced by weak interactions such as π…π packing and hydrogen bonds. The characterization shows that CPs 1 and 2 have good fluorescence deletion properties, crystallinity, thermodynamic stability, and structural integrity, and can be used as fluorescence sensing materials. 1 and 2 have fluorescence recognition ability for Zr⁴⁺, Cr₂O₇^2- and Fe³⁺, HPO₄^2- in aqueous solution, respectively, with good selectivity and high sensitivity. The detection limits of these four ions by 1 and 2 were 0.139 μmol·L^-1 (1, Zr⁴⁺), 0.626 μmol·L^-1 (1, Cr₂O₇^2-), 0.430 μmol·L^-1 (2, Fe³⁺), 1.36 μmol·L^-1 (2, HPO₄^2-), respectively. The fluorescence quenching mechanism of 1 and 2 as probes was investigated in detail. More interestingly, the two complexes have potential fingerprint recognition properties. Their fluorescent fingerprint patterns were clear and coherent, and the details were obvious and could be clearly observed.