Phosphorescent Ionic Iridium(III) Complexes Displaying Counterion-Dependent Emission Colors for Flexible Electrochromic Luminescence Device

4 years ago

Phosphorescent Ionic Iridium(III) Complexes Displaying Counterion-Dependent Emission Colors for Flexible Electrochromic Luminescence Device

Rui Jiang, Pengfei She, Shujuan Liu, Jin Yang, Yun Ma, Qiang Zhao, Huiting Xia

Stimulus-responsive luminescent materials have drawn considerable interest because they are ideal candidates for optoelectronic applications. Herein, a series of phosphorescent iridium(III) complexes [(CZPY)2IrNH]+X− (X− = PF6−, I−, Br−, Cl−) containing two NH moieties in the N^N ligand is reported. These complexes exhibit significantly counterion-dependent emission color change from green (493 nm) to orange (590 nm) in CH3CN. Besides, the emission color of [(CZPY)2IrNH]+PF6− is sensitive to the external electric field. Upon applying a voltage, the emission color of the complex in solution is changed evidently from orange to green at the cathode within several seconds. Moreover, with the advantages of high ionic conductivity, thermal stability, and mechanical strength, a bisimidazolium-based polymeric ionic liquid is designed and synthesized as the electrolyte. Ultimately, a flexible electrochromic luminescence device is successfully fabricated, which exhibits excellent performance and properties, such as good flexibility, low operation voltage, fast response time, and good reversibility. A series of phosphorescent iridium(III) complexes containing different counterions is prepared, which exhibit wide counterion-dependent emission wavelength tuning up to ≈100 nm and excellent electrochromic luminescence (ECL). By combining a bisimidazolium-based polymeric ionic liquid, an ECL device is fabricated, which exhibits excellent performance, such as flexibility, low operation voltage, fast response, as well as good reversibility.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/adom.201700587