Organic Semiconductors with Helical Structure Based on Oligothiophene derivatives Exhibiting Chiral Nematic Phase
摘要:
We have synthesized 2-[5-(4-[(S)-2-methylbutoxy]phenyl)-3-methyl]-2'''-propyl-2: 5'-2'-5 ''-2 ''-5"'-quaterthiophene (10), a liquid crystalline semiconductor that exhibits a chiral nematic phase, and used the time-of-flight technique to determine its carrier mobility behavior. In the chiral nematic phase, the positive carrier mobility was 2 x 10(-4)cm(2)/Vs at 120 degrees C and the negative carrier mobility was 1 x 10-4 cm(2)/Vs, both of which we attribute to electronic processes. For the negative carrier, in addition to the fast electronic process, we also observed a slow carrier transport, having mobility on the order of 10(-5)cm(2)/Vs, which we attribute to ionic conduction. Chiral dimers containing binaphthyl group exhibited stable glassy cholesteric phase and cholesteric thin films with selective reflection band in visible light area could be fabricated. They emitted circularly polarized light with dichroic parameter of 1.3 when UV light was illuminated.
Organic Semiconductors with Helical Structure Based on Oligothiophene derivatives Exhibiting Chiral Nematic Phase
作者:Masahiro Funahashi、Nobuyuki Tamaoki
DOI:10.1080/15421400701735723
日期:2007.12.13
We have synthesized 2-[5-(4-[(S)-2-methylbutoxy]phenyl)-3-methyl]-2'''-propyl-2: 5'-2'-5 ''-2 ''-5"'-quaterthiophene (10), a liquid crystalline semiconductor that exhibits a chiral nematic phase, and used the time-of-flight technique to determine its carrier mobility behavior. In the chiral nematic phase, the positive carrier mobility was 2 x 10(-4)cm(2)/Vs at 120 degrees C and the negative carrier mobility was 1 x 10-4 cm(2)/Vs, both of which we attribute to electronic processes. For the negative carrier, in addition to the fast electronic process, we also observed a slow carrier transport, having mobility on the order of 10(-5)cm(2)/Vs, which we attribute to ionic conduction. Chiral dimers containing binaphthyl group exhibited stable glassy cholesteric phase and cholesteric thin films with selective reflection band in visible light area could be fabricated. They emitted circularly polarized light with dichroic parameter of 1.3 when UV light was illuminated.