Synthesis and Characterization of Novel Triarylamine Derivatives with Dimethylamino Substituents for Application in Optoelectronic Devices

Two
novel triphenylamine-based derivatives with dimethylamino substituents, N,N′-bis­(4-dimethylaminophenyl)-N,N′-bis­(4-methoxyphenyl)-1,4-phenylenediamine
(NTPPA) and N,N′-bis­(4-dimethylaminophenyl)-N,N′-bis­(4-methoxyphenyl)-1,1′-biphenyl-4,4′-diamine
(NTPB), were readily prepared for investigating the optical
and electrochromic behaviors. These two obtained materials were introduced
into electrochromic devices accompanied with heptyl viologen (HV), and the devices demonstrate a high average coloration
efficiency of 287 cm2/C and electrochemical stability.
Besides, NTPB/HV was further used to fabricate
electrofluorochromic devices with a gel type electrolyte, and exhibit
a controllable and high photoluminescence contrast ratio (Ioff/Ion) of 32.12
from strong emission to truly dark by tuning the applied potential
in addition to a short switching time of 4.9 s and high reversibility
of 99% after 500 cycles.