Oxygen sensing nanofibers doped with red-emitting Eu(III) complex: Synthesis, characterization, mechanism, and sensing performance

摘要

In this paper, we synthesize a novel diamine ligand of PIP and its corresponding Eu(III) complex of Eu(DBM)_3PIP, where PIP = 2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline, and DBM = 1,3-diphenyl-propane-1,3-dione. The UV-Vis absorption spectra, low temperature phosphorescence spectra, energy transfer mechanism, excited state lifetime of Eu(DBM)_3PIP, as well as its photoluminescence spectra, are investigated in detail. Data suggest that the emission of Eu(DBM)_3PIP is quenchable by molecular oxygen due to the back-energy transfer process. By doping Eu(DBM)3PIP into a polymer matrix of poly(vinylpyrrolidone) (PVP), the oxygen sensing performance of the resulted nanofibrous membrane is investigated. Finally, the 0.6 wt% doped sample exhibits a linear response towards molecular oxygen, with a sensitivity of 3.5 and response/recovery time of 15 s/24 s.