The multi-color switching of electrofluorochromism was examined from the thin electrofluorochromic (EF) films of polyfluorene (PFO) and poly(propylenedioxythiophene-phenylene) (P(ProDOT-Ph)). The PFO and P(ProDOT-Ph) films showed vivid blue and yellow fluorescence, respectively, at neutral state but their emission was quenched upon application of oxidation potential leading to ion radical states. The fluorescence from the polymer films was reversibly switched to vivid color when the films were returned to their neutral states. The EF color switching ratio (rc1/c2) between the fluorescent state (c1) and dark (c2) state for the yellow color EF device with P(ProDOT-Ph) film was about four times higher than that of the PFO. Because the two polymer films have different colors and working potentials, a multi-color switching device was fabricated by coating the P(ProDOT-Ph) and PFO films onto working and counter electrodes, respectively. The multi-color EF device showed fluorescence switching from blue (B) to white (W) to yellow (Y), and vice versa, depending on the applied potential. The rc1/c2 for yellow (c1) and blue (c2) switching (Y/B) was larger (9.71) than those for Y/W and W/B. Moreover, the EF switching for Y/B in the multi-EF device was also very effective and showed the largest EF efficiency (EEF = 3.82 × 106) among the EF color switching.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation (NRF) grant funded by the Korean government (Ministry of Science, ICT & Future Planning, MSIP) (2015M3D1A1069197 and 2015H1D3(a)1066519). This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HI15C0942). This work was supported (in part) by the Yonsei University Research Fund (Post Doc. Researcher Supporting Program) of 2015 (project no.: 2015-12-0003).
© 2016 Optical Society of America.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials