Re(I) complex doped nanofibers for oxygen optical sensing

In this paper, we design and synthesize a novel diamine ligand of PTO (2-(pyridin-2-yl)-5-p-tolyl-1,3,4-oxadiazole). The crystal structure, photophysical character and electronic nature of its corresponding Re(I) complex of Re(CO)3(PTO)Br have been investigated in detail. Experimental data and theoretical calculation suggest that Re(CO)3(PTO)Br owns a long-lived yellow phosphorescence which is sensitive towards molecular oxygen. By doping Re(CO)3(PTO)Br into a polymer matrix of polystyrene (PS), the emission response of the resulted composite nanofibers towards molecular oxygen is studied. The optimal sample with mean diameter of 600 nm shows a maximum sensitivity of 4.14 with short response time of 14 s (here sensitivity is defined as the ratio of emission intensity in pure N2 atmosphere to that in pure O2 atmosphere). The composite nanofibers are also found to be photostable enough to experience UV radiation.

A Re(I) complex with oxadiazole-derived diamine ligand was synthesized, hoping to achieve an optical sensor with longer excited state lifetimes and higher photostability. By doping it into a polymer matrix, oxygen sensing performances of the resulted composite materials were investigated. Finally, a high sensitivity of 4.14 was realized, with a short response/recovery time of 14 s/21 s.Figure optionsDownload as PowerPoint slideHighlights
► An oxadiazole-derived diamine ligand and its Re(I) complex were reported.
► Crystal structure, photophysical property and electronic nature were studied.
► It owned a long excited state lifetime favoring oxygen sensing.
► It was doped into a polymer matrix to give composite nanofibers.
► A maximum sensitivity of 4.14 with short response time of 14 s was realized.