Electrospinning fibrous films doped with iridium complexes for high performance oxygen sensing: Synthesis and characterization

•Three Ir(III) complexes with various fluorine atoms in their ligands were reported.•The presence of F atoms increased lifetime of excited electrons and favored O2 sensing performance.•O2 sensing materials were obtained by doping these Ir(III) complexes into a polymer host.•Improved sensitivity and linear response were obtained from these sensing materials.

This work was devoted to three Ir(III) complexes having large conjugation planes and various numbers of fluorine substituents for optical oxygen sensing purpose. These F atoms might broaden electronic distribution of excited electrons and increase their decay lifetime, hoping to increase sensing collision probability of excited electrons with O2 molecules. These Ir(III) complexes were analyzed by single crystal analysis and density functional theory calculation. Photophysical measurement suggested that their phosphorescent emission was quenchable by O2 gas. By doping these Ir(III) complexes into fibrous films through electrospinning method, their oxygen sensing performance was explored. The presence of F atoms improved oxygen sensing performance. High sensitivity (12.89), short response (8 s), good stability and, more importantly, linear response were observed.

Graphical abstractThree Ir(III) complexes with large conjugation planes and various numbers of fluorine substituent were reported for optical oxygen sensing purpose. The presence of F atoms broadened electronic distribution of excited electrons and increased their decay lifetime, increasing sensing collision probability with O2 molecules. High sensitivity (12.89), short response (8 s), good stability and, more importantly, linear response were obtained.Download high-res image (104KB)Download full-size image