Conjugated polymers containing selenophene have received attention due to their unique properties and promising application in organic electronics. Herein, to further improve the optoelectronic properties, two typical selenophenes containing [1,2,5]thiadiazolo[3,4-c]pyridine (PT)/[1,2,5]selenadiazolo[3,4-c]pyridine (PS) were synthesized by a donor–acceptor strategy and electropolymerized to form the donor–acceptor–donor polymers. The two precursors exhibited yellow and red emission characteristics with high quantum yields (∼0.48); the value was far greater than those for previously reported selenophenes. Furthermore, electrochromic studies demonstrated that the obtained polymers have superior coloration efficiencies (168 cm−2 C−1) than thiophene based analogues and fast response times (1.6 s).
![Graphical abstract: [1,2,5]Chalcogenodiazolo[3,4-c]pyridine and selenophene based donor–acceptor–donor electrochromic polymers electrosynthesized from high fluorescent precursors](http://hg.y866.cn/compound/lib/scimg/usr/1/C5NJ03432A.jpg)