Electrochemical and Optical Properties of D-A-A-A-D Azomethine Triad and Its NIR-Active Polymer.

The azomethine with a donor-acceptor-acceptor-acceptor-donor structure has been synthesized and characterized. Azomethine exhibited luminescence properties and a positive solvatochromic effect. Electropolymerization on terminated triphenylamine groups was used to obtain a thin layer of the polyazomethine . Further investigation of oxidation/reduction properties of via cyclic voltammetry showed that the polymer undergoes two reversible oxidation/reduction processes due to the presence of tetraphenylbenzidine moieties. Electrochromic properties of the polyazomethine were investigated via spectroelectrochemistry. It was observed that the polymer in its neutral state is orange, and the color changes to green upon electro-oxidation. The stability of the polymer during multiple oxidation/reduction cycles, response times, and coloration efficiency were also investigated.