Solvent effects on the synthesis, characterization and electrochromic properties of acetic acid modified polyterthiophene

Thiophene-Based Trimers and Their Bioapplications: An Overview

Certainly, the success of polythiophenes is due in the first place to their outstanding electronic properties and superior processability. Nevertheless, there are additional reasons that contribute to arouse the scientific interest around these materials. Among these, the large variety of chemical modifications that is possible to perform on the thiophene ring is a precious aspect. In particular, a turning point was marked by the diffusion of synthetic strategies for the preparation of terthiophenes: the vast richness of approaches today available for the easy customization of these structures allows the finetuning of their chemical, physical, and optical properties. Therefore, terthiophene derivatives have become an extremely versatile class of compounds both for direct application or for the preparation of electronic functional polymers. Moreover, their biocompatibility and ease of functionalization make them appealing for biology and medical research, as it testifies to the blossoming of studies in these fields in which they are involved. It is thus with the willingness to guide the reader through all the possibilities offered by these structures that this review elucidates the synthetic methods and describes the full chemical variety of terthiophenes and their derivatives. In the final part, an in-depth presentation of their numerous bioapplications intends to provide a complete picture of the state of the art.

Benzothiadiazole bridged EDOT based donor-acceptor polymers with tunable optical, electrochemical, morphological and electrochromic performance: effects of solvents and electrolytes

Donor-acceptor (D-A) polymers have been widely studied for their tunable electronic properties, however, it is surprising that systematic studies on the effect of different solvents and electrolytes on their opto-electrochemical, morphological and electrochromic performance have drawn only little attention. In the presented work, nine different D-A polymer films, poly(4,7-di(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)benzo[1,2,5]thiadiazole) (a-i-P1), were electrosynthesised using different polar solvents (PC, MeCN and DCM) and supporting electrolytes (TBAPF6, TBAClO4 and TBABF4). A thorough study of these D-A polymer films using cyclic voltammetry, UV-Vis-NIR spectroscopy, FE-SEM, spectroelectrochemistry and electrochromic techniques has been performed. We found a significant effect of both the supporting electrolytes and solvents on the morphology of polymer films which correlates well with their opto-electronic properties. Films prepared using the TBAClO4/PC system show a smooth morphology with a significantly high coloration efficiency of 264 cm2 C-1 and an optical contrast of 65.3%. Such differences in the optical and electrochemical properties of polymer films were explained by the ion pair formation during polymerisation.