Chemistry Reference
In-Depth Information
H
17
C
8
C
8
H
17
N
N
S
O
N
O
N
O
The four copolymers that were synthesized contained different acceptor end groups, aldehyde,
monocyano, dicyano, and 1,3-diethyl-2-thiobarbituric acid. Through changing the acceptor groups,
the electronic properties and energy levels of the copolymers were effectively tuned. Their results
indicate that it is an effective approach to tuning the bandgaps in conjugated polymers. The polymers
were used as donors in polymer solar cells. They reported, however, conversion efficiency of only
2.76%.
You and coworkers [
276
] reported syntheses of two low-band gap polymers based on benzo(1,2-
b
:4,5-
b
)dithiophene:
R
1
S
S
S
S
R
2
N
R
2
N
R
1
S
where R
1
¼
3-butylnonyl and R
2
¼
nonyl and in the send polymer, R
1
¼
3-hexylundecyl and
R
2
¼
hydrogen.
Both polymers were reported to have performed well in preliminary bulk heterojunction solar
cells, reaching power conversion efficiency greater than 4%.
Jenekhe, Watson, and coworkers [
277
] reported synthesizing three new donor-acceptor conjugated
polymers
]pyrrole-4,6-dione acceptor and dialkoxybithiophene or
cyclopentadithiophene donor units. The thieno[3,4-
incorporating thieno[3,4-
c
]pyrrole-4,6-dione acceptor containing materials
were studied in bulk heterojunction solar cells and organic field-effect transistors. The polymers had
c
