Spectroscopic and Electrochemical Studies on Photoactive Thin Films of Poly (2,5-Di(2-thienyl)-1H-pyrrole) (PSNS) in Gel Electrolytes: Influence of the Pyrrole NH Group
Photo-electrochemical (PEC) and spectroscopic studies were conducted on poly (2,5-di(2-thienyl)-1H-pyrrole) (PSNS) in a gel electrolyte. The results were compared with those of 2,2’-bithiophene (PBTh). The results show that incorporating a pyrrole ring into a pure thiophene monomer produces a polymer that shows no hole accumulation and exhibits random electron-hole pair production in its PEC. Absorption spectra indicate that PSNS has a band gap that ranges from 2.3 to 3.1 eV, whereas DFT calculations show that pure PSNS has an approximate band gap of 2.0 eV. Furthermore, EIS studies reveal that PSNS exhibits lower real impedance than PBTh. This can be correlated to several factors such as porosity, doping, and the morphology of each polymer. Both studied polymers were electrochromic and exhibited fluorescence emission. The gel electrolyte demonstrates sustainable functionality, evidenced by the reproducible photo-electrochemical results.
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