A Novel Electrochromic Polymer Synthesized through Electropolymerization of a New Donor−Acceptor Bipolar System

Abstract

We have synthesized a novel 9,9′-spirobifluorene-cored donor-acceptor (D-A) bichromophore system in which the electron-donating (D) moieties are triphenylamine (TPA) and carbazole (CBZ) groups and the electron-withdrawing (A) moieties are 1,3,4-oxadiazole (OXD) groups. The electron-deficient OXD groups efficiently blocked the radical cations delocalization between the two terminal TPA groups, rendering the electropolymerization of the TPA groups feasible. The resulting polymer could be cross-linked further at higher oxidation potentials through electrodimerization occurring at the C3 and C6 positions of the CBZ group. The polymer film obtained exhibited reversible electrochemical oxidation, accompanied by strong color changes with high coloration efficiency and contrast ratio, which could be switched through potential modulation.

Synthesis, crystal structure, photophysical property and electropolymerization of Pt(II) complexes with carbazole-grafting 2-(2-pyridyl)benzimidazole

“…722 nm with positive increase of the applied potential. This result is in agreement with that of the oxidized biscarbazole reported previously [33], reconfirming that the dimerization of the carbazole moiety of PBC is involved in the electropolymerization process. The polymer film underwent a clear color change from pale green to dark green, suggesting its promising potential in electrochromic materials.…”

Spray Processable Green to Highly Transmissive Electrochromics via Chemically Polymerizable Donor–Acceptor Heterocyclic Pentamers

“…In spite of the considerable impact of this discovery for device applications such as field-effect transistors, [2][3][4] light emitting diodes [5] and photovoltaics, [6][7][8][9] only recently has the use of donor-acceptor based conducting polymers attracted the attention of research groups with an interest in electrochromic polymers (ECPs). [10][11][12][13][14] On the other hand, the last two decades have seen a particular stress placed on incorporating ECPs as fast and reversible color changing materials in devices such as windows, mirrors and displays. [15] While a number of neutral state red and blue conjugated polymers were synthesized and their properties investigated, [16][17][18] attempts in making saturated green polymers, chemically or electrochemically synthesized, have met limited success [15] due to the complex nature of the required absorption spectrum that must contain at least two bands in the neutral state of the material.…”

Effective adjustment of the optoelectronic properties of organic conjugated materials by synthesizing p-n diblock molecules

“…The electron-deficient OXD groups efficiently blocked the radical cation delocalization between the two terminal TPA groups, rendering the electropolymerization of the TPA groups feasible (Figure 33). The polymer films made of 80 and 81 exhibited reversible electrochemical oxidation, accompanied by strong color changes with high coloration efficiency and contrast ratio that could be switched through potential modulation [78]. Electrodeposition of spirobifluorene p-n diblock systems is a versatile tool for tuning the electrode surface work function [79].…”