Synthesis, characterization and electrochemical properties of polybiselenophene

Electrosyntheses of high quality freestanding polyselenophene films in boron trifluoride diethyl etherate

“…The absorption near UV region can be ascribed to the p ! p* interband transition, indicating that the band gap of neutral PSe was about 2.5 eV, in accordance with those of PSe prepared from biselenophene monomer [50]. Theoretical calculations showed that the band gap of neutral PSe is about 2.0 eV [17,18].…”

“…The higher electron donating character of selenophene implied that different composition of heteroatoms in similar systems could differ greatly in their electrical properties, chemical stability and ease of polymerization. Therefore, the syntheses and characterizations of polyselenophene (PSe) were investigated in previous studies, such as the theoretical calculations of band gap and vibration spectra of PSe [16][17][18][19][20][21][22][23][24][25], the chemical polymerization [26][27][28][29][30][31][32][33][34], and the electrochemical polymerization [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51]. However, the high monomer oxidation potential in common solvent such as acetonitrile made the preparation of high quality PSe very difficult and the overoxidation resulted in the damage of conjugated PSe backbone, thus leading to powdery PSe formation with conductivity of only 3.7 · 10 À2 S cm À1 [39].…”

“…In order to overcome this problem, various approaches were tested, for instance, the substitution of electron donating groups on b-position of selenophenes, poly(3-alkylthiophene) [52][53][54][55][56][57][58], poly(3,4-ethylenedioxyselenophene) [59]. The derivatives like poly(biselenophene) [50,51], poly[1,2-bis(2-seleninyl)ethane] [60][61][62], oligoselenophenes [63][64][65][66] and the copolymers [67] with pyridine [68,69] were also tested for polymerization and the characterizations of corresponding polymers with special properties, such as nonlinear optical [70,71]. Although these modifications showed improved quality of as-formed PSe and its derivatives, the preparation of the initial substituted selenophene monomers was very complex.…”

Spectroelectrochemistry of Intrinsically Conducting Selenophene-3-Chlorothiophene Copolymers

“…10% of TFA (v/v) containing Se/ChrTh (mole ratio 1:1); for comparison, the data of the respective homopolymers are included in Table 3. The spectra of the pristine homopolymers are in agreement with the previously published in the literature 3,23,24,43 with typical bands for five bonded heterocycles are observable in their IR spectra. The two homopolymers have C=C stretching vibration mode between 1400-1600 cm representing that selenophene and 3-chlorothiophene rings are remained jointly after polymerization.…”

“…652 nm) of the spectrum to be about 1.90 eV. This value is close to the reported band gap energy of electropolymerized poly(biselenophene) 43 and polyselenophene. 10,44 The passage from the undoped to the doped state is accompanied by weakening of the interband transition.…”