High‐Performance Electrofluorochromic Devices Based on Electrochromism and Photoluminescence‐Active Novel Poly(4‐Cyanotriphenylamine)

Abstract

A novel electrochromism (EC) and photoluminescence (PL)‐active poly(4‐cyanotriphenylamine) (CN‐PTPA) is prepared by oxidative coupling polymerization from 4‐cyanotriphenylamine (CN‐TPA) using FeCl3 as an oxidant. The high‐performance electrofluorochromic (EFC) devices using CN‐PTPA thin film with photoluminescent quantum yield of 21.9% as active layer are readily fabricated and reveal the highest fluorescent contrast ratio (I off/I on) of 242 between the fluorescent (neutral) state and the non‐fluorescent (oxidized) state, rapid response time shorter than 0.4 s, and excellent EFC stability longer than 9000 s. Furthermore, by introducing viologen into electrolyte as a counter EC layer for charge balance, the resulting EFC device exhibits notable improvement in reducing oxidation potential (from 2.30 V to 1.55 V) and switching recovery time (from 78 to 38 s) with enhanced fluorescent contrast ratio during pulse on/off multi‐cyclic scanning. These results demonstrate that incorporation of the EC and PL‐active CN‐PTPA is a facile and feasible approach to prepare highly efficient EFC devices.

Photoinduced electron transfer as a design concept for luminescent redox indicators

“…Rather than focusing on the switching parameters in solution, the authors study the photoelectric conversion of thin films of 15 on ITO-coated glass. 58 The BODIPY-based fluorescent sensor 17 (Fig. A notable example is 16 with an uncharacteristic oxygen atom between the triphenylamine and tetrazine (Fig.…”

Electroswitchable optical device enabling both luminescence and coloration control consisted of fluoran dye and 1,4-benzoquinone

“…Among these multifunctional materials, electrical stimuliresponsive molecules are particularly suitable for display applications because the electrical stimuli can be applied rapidly and reversibly [39][40][41][42][43][44][45]. Because of these advantages, electrical stimuli have attracted much attention.…”

Influence of donor-acceptor conjugation between thiophene-phthalazinone structures containing Sp3 CN bond on the frontier orbital levels and optic-electronic properties

“…In the past decades, the intrinsic characteristics of donor–acceptor (D–A) conjugated polymers containing Sp 3 CN bond have been widely studied as important organic semiconductor materials for optoelectronic applications, such as light‐emitting diodes, polymer solar cells, and organic field effect transistors . The classical structures, such as polyaniline and triphenylamine, are shown in Figure .…”

“…Also, polymeric materials based on triphenylamine units have been widely used as semiconductor materials for electro‐optics applications. The structure feature of triphenylamine is that the electron‐rich nitrogen atom links with three π‐conjugated phenyl groups, resulting in its narrower band gaps than that of non‐doped polyaniline. Incorporating triphenylamine into polymer backbones with π‐conjugated system could obtain excellent charge‐transport, hole‐transporting, and electroluminescence properties with controllable band gaps .…”