A luminescent Eu coordination polymer with near-visible excitation for sensing and its homologues constructed from 1,4-benzenedicarboxylate and 1H-imidazo[4,5-f][1,10]-phenanthroline

摘要: A Eu-coordination polymer and its homologues, namely, five lanthanide coordination polymers (Ln-CPs), [Ln(BDC)1.5(IP)(H2O)]·nH2O (Ln = Sm 1, Eu 2, Gd 3, Tb 4, Dy 5), were constructed from 1,4-benzenedicarboxylate (BDC) 1H-imidazo[4,5-f][1,10]-phenanthroline (IP). They feature 2D network structures with LnO6N2 units by bridging BDC ligands, while the IP molecules as terminal ligands are coordinated to Ln(III) ions in bidentate chelating mode. The luminescence of these compounds was recorded. Eu-CP has several distinct advantages including a broad excitation band (315 nm < λex 410 nm) maximum wavelength up 375 nm, visible red emission, good aqueous stability wide pH range 4–10. Using chemical sensor, high sensing for emodin medium realized at nm. Remarkably, when excited 400 light, also exhibited similar capacity. UV-vis absorption spectral studies density functional theory (DFT) calculations performed elucidate possible mechanism quenching emodin. Similarly, detection common (Fe3+, Ag+, Cr2O72−/CrO42−, MnO4−) under near-visible light or experimental results prove that is an excellent luminescent compound, can be adjusted (350 nm), strong analytes achieved.