Premium
Effects of Block Length in Copolymers Based on Regioregular Oligothiophenes Linked With Electron‐Accepting Units
Author(s) -
Zhang Luozheng,
Zhang Yue,
Wei Qingshuo,
Zhou Erjun,
Yang Chunhe,
Hashimoto Kazuhito,
Tajima Keisuke
Publication year - 2012
Publication title -
macromolecular rapid communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.348
H-Index - 154
eISSN - 1521-3927
pISSN - 1022-1336
DOI - 10.1002/marc.201100827
Subject(s) - copolymer , materials science , stille reaction , quantum efficiency , organic solar cell , pyrrole , conjugated system , polymer chemistry , absorption spectroscopy , photochemistry , polymer , chemistry , optoelectronics , organic chemistry , optics , physics , composite material
Copolymers with an alternating structure of regioregular oligo(3‐hexylthiophene) (O3HT) with different lengths and 2,5‐dibutyl‐3,6‐di(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione (DPP) were synthesized through Stille coupling reaction. The light absorption of the copolymers can be rationally tuned to have a broad spectrum across the visible region by adjusting the length of O3HT. Organic solar cells fabricated with the copolymers and PCBM showed a broad photoresponse and a comparable efficiency to that of poly(3‐hexylthiophene) (P3HT):PCBM cells. The external quantum efficiency and fluorescence spectra suggested that the intrachain energy transfer from the O3HT block to the vicinity of the DPP unit could limit the photovoltaic performance of the copolymers.