Synthesis, electrochromic, halochromic and electro-optical properties of polyazomethines with a carbazole core and triarylamine units serving as functional groups

Abstract

A series of aromatic polyazomethines (PAMs) were prepared via the direct polycondensation from 9-(2-ethylhexyl)-carbazole-3, 6-dicarboxaldehyde and six different kinds of diamine containing triarylamines. The PAMs displayed good solubility in many organic solvents such as tetrahydrofuran (THF), chloroform (CHCl 3 ), N,N-dimethylformamide (DMF), et al which was beneficial for polymer film formation via spin coating, and exhibited outstanding thermal stability.These PAMs exhibited blue-green photoluminescence around 405-520 nm with quantum yield up to 48 % in dichloromethane (CH 2 Cl 2 ) solution. They exhibited halochromic properties with color changing from yellow to red, and accompanied by fluorescence quenching after HCl-doped. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of these PAMs were determined from cyclic voltammograms as -5.01 to -4.88 eV and -2.15 to -2.11 eV, respectively. The PAMs films not only had good electrochromic properties with high coloration efficiency, but also generated photovoltagic and photocurrent under simulated solar radiation.

Accessible microwave synthetized conjugated poly(azomethine‐pyridine) network and its metal complexes for CO2 conversion

“…Aromatic poly(azomethines) ( PAMs ), also known as poly(imines) or Schiff base polymers are conjugated networks with interesting characteristics such as high thermal stability, semiconductivity, or optoelectronic properties which make them attractive candidates for electronic and optoelectronic devices, such as photovoltaic cells, light‐emitting diodes, or thin‐film transistors . However, the high rigidity of these aromatic polymers and the poor solubility in organic solvents has limited their practical applications.…”

Hydrogen‐Bond and Supramolecular‐Contact Mediated Fluorescence Enhancement of Electrochromic Azomethines

“…This has been further spurred by their properties, which are ideally suited for use as functional materials in plastic electronics. For example, conjugated derivatives have been successfully used as active layers in organic photovoltaics and electrochromic devices . Although property tailoring is possible through the judicious selection of aromatics used for their preparation, a key azomethine property that remains elusive is high fluorescence quantum yields ( Φ fl ).…”

Arylamine polymers prepared via facile paraldehyde addition condensation: an effective hole‐transporting material for perovskite solar cells

“…These durable redox properties suggested that carrier generation might occur in the solid state. MPA showed a two‐step reversible redox reaction, consisting of one‐electron oxidized arylammonium cation radical formation and two‐electron oxidized dication formation …”