Novel Display Device with Dual Emissive and Reflective Modes by Using Luminescent Lanthanide (III) Complexes and Electrochromic Materials

Abstract

A novel display device with dual emissive and reflective display mode (dual-mode display) was demonstrated. The novel device was based on electrochromic reaction as reflective mode and photoluminescence as emissive mode. An electrochromic molecule of viologen derivative and an luminescent lanthanide (III) complex were introduced for achieving dual-mode representation. The device functioned as an electrochromic device when bias voltage was applied and as a light-emitting device if excitation lights are irradiated. When bias voltage was applied to the device, cell color was changed from clear transparent to cyan color by electrochromic reaction of the viologen derivatives. On the other hand, under UV irradiation, strong red emission was observed from the lanthanide (III) complex. The emission intensity could be controlled by electrochromic reaction of viologen derivatives.