Tuning the Band Gap of Low-Band-Gap Polyselenophenes and Polythiophenes: The Effect of the Heteroatom
摘要:
A series of new low-band-gap thieno- or selenolo-fused polyselenophenes (P5 and P6) and selenolo-fused polythiophene (P4) (as well as previously reported thieno-fused polythiophene, P3) was prepared systematically by electropolymerization (P4-P6) and by solid-state polymerization (P3, P5 and P6). The 2,5-dibrominated monomers (3Br(2), 5Br(2), and 6Br(2)) undergo solid-state polymerization under slight heating and produce insoluble P3, P5, and P6 as black conducting powders. The spectroelectrochemically measured optical band gaps of P4-P6 films are 0.96, 0.72, and 0.76 eV, respectively. DFT calculations performed on P3-P6 provide excellent estimations of the experimental band gaps of these polymers. The band gap of the polyselenophenes (P5 and P6) is 0.2 eV lower than that of the corresponding polythiophenes (P3 and P4). We introduced a new scheme for band gap control in conjugated polymers by replacing the sulfur atom with a selenium atom in the main and/or peripheral ring, which leads to significant and predictable changes in the band gap of the polymers. This is due to the lower aromaticity of a selenophene ring compared to a thiophene ring. Thus, we have achieved band gap control in very low band gap (similar to 0.7-1.0 eV) polymers through the use of different combinations of selenium and sulfur atoms in the main and peripheral rings.
Selenolo [3,4- b ]硒烯(3)已经通过两种不同的路线,以2,3-双氯甲基-5-碳甲氧基硒烯(4)或优选4-甲基硒-3-硒烯醛(10)为起始原料合成。与其噻吩类似物相反,噻吩并[3,4- b ]噻吩3是稳定的。所述的分析1个H,13 C和,特别是77硒NMR得到强有力的证据为硒-5的更积极的性质比的硒-1原子3。
A heterocyclic fused selenophenes and a method of making a heterocyclic fused selenophenes of formula (1):
wherein X is S or Se, Y is S or Se, wherein one or both of X and Y is Se, R is a substituent group. The monomer being capable of polymerization to form an electrically conductive polymer or oligomer.
Synthese der kondenisierten Selenophene durch Einwirkung von Acetylen auf Selen
作者:Sumio Umezawa
DOI:10.1246/bcsj.14.363
日期:1939.9
KONAR A.; GRONOWITZ S., TETRAHEDRON, 1980, 36, NO 22, 3317-3323
作者:KONAR A.、 GRONOWITZ S.
DOI:——
日期:——
KONAR, A., CHEM. SCR., 1983, 22, N 4, 177-181
作者:KONAR, A.
DOI:——
日期:——
Tuning the Band Gap of Low-Band-Gap Polyselenophenes and Polythiophenes: The Effect of the Heteroatom
作者:Asit Patra、Yair H. Wijsboom、Gregory Leitus、Michael Bendikov
DOI:10.1021/cm102395v
日期:2011.2.8
A series of new low-band-gap thieno- or selenolo-fused polyselenophenes (P5 and P6) and selenolo-fused polythiophene (P4) (as well as previously reported thieno-fused polythiophene, P3) was prepared systematically by electropolymerization (P4-P6) and by solid-state polymerization (P3, P5 and P6). The 2,5-dibrominated monomers (3Br(2), 5Br(2), and 6Br(2)) undergo solid-state polymerization under slight heating and produce insoluble P3, P5, and P6 as black conducting powders. The spectroelectrochemically measured optical band gaps of P4-P6 films are 0.96, 0.72, and 0.76 eV, respectively. DFT calculations performed on P3-P6 provide excellent estimations of the experimental band gaps of these polymers. The band gap of the polyselenophenes (P5 and P6) is 0.2 eV lower than that of the corresponding polythiophenes (P3 and P4). We introduced a new scheme for band gap control in conjugated polymers by replacing the sulfur atom with a selenium atom in the main and/or peripheral ring, which leads to significant and predictable changes in the band gap of the polymers. This is due to the lower aromaticity of a selenophene ring compared to a thiophene ring. Thus, we have achieved band gap control in very low band gap (similar to 0.7-1.0 eV) polymers through the use of different combinations of selenium and sulfur atoms in the main and peripheral rings.