Conventional solution electrochemluminescent (SECL) cells have a low luminance. In this research, we propose an ion conductive assistant dopant (ICAD) system to improve the luminance of SECL cells. The solution of the cell consists of mixed solvent (o-dichlorobenzene/acetonitrile=2/1 (vol/vol)), rubrene used as the emitting material and 1,2-diphenoxyethane used as the ICAD. When voltage is applied to this SECL cell, the cell achieves a luminance of 183cd/m^2 and a luminous efficiency of 1.5cd/A at 8V with yellow emission. On the other hand, an SECL cell without an ICAD results in a low luminance of 0.3cd/m^2 at 8V, corresponding to a conventional SECL cell. The ICAD improves the luminance 600 times by enhancing the ion conduction of rubrene cations in the solution. Furthermore, when the mixed solvent (o-dichlorobenzene/toluene=2/1(vol/vol)), which has a high voltage resistance, is used in the SECL cell, the cell obtains a maximum luminance of 986 cd/m^2 at 80V. The features of the SECL cell are a simple cell structure and a transparent emitting area. SECL cells are expected to be used in unique displays with a see-through function.
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