TY - JOUR
T1 - An Alkylated Indacenodithieno[3,2-b]thiophene-Based Nonfullerene Acceptor with High Crystallinity Exhibiting Single Junction Solar Cell Efficiencies Greater than 13% with Low Voltage Losses
AU - Fei, Zhuping
AU - Eisner, Flurin D.
AU - Jiao, Xuechen
AU - Azzouzi, Mohammed
AU - Röhr, Jason A.
AU - Han, Yang
AU - Shahid, Munazza
AU - Chesman, Anthony S. R.
AU - Easton, Christopher D.
AU - McNeill, Christopher R.
AU - Anthopoulos, Thomas D.
AU - Nelson, Jenny
AU - Heeney, Martin
PY - 2018/2/22
Y1 - 2018/2/22
N2 - A new synthetic route, to prepare an alkylated indacenodithieno[3,2-b]thiophene-based nonfullerene acceptor (C8-ITIC), is reported. Compared to the reported ITIC with phenylalkyl side chains, the new acceptor C8-ITIC exhibits a reduction in the optical band gap, higher absorptivity, and an increased propensity to crystallize. Accordingly, blends with the donor polymer PBDB-T exhibit a power conversion efficiency (PCE) up to 12.4%. Further improvements in efficiency are found upon backbone fluorination of the donor polymer to afford the novel material PFBDB-T. The resulting blend with C8-ITIC shows an impressive PCE up to 13.2% as a result of the higher open-circuit voltage. Electroluminescence studies demonstrate that backbone fluorination reduces the energy loss of the blends, with PFBDB-T/C8-ITIC-based cells exhibiting a small energy loss of 0.6 eV combined with a high JSC of 19.6 mA cm−2.
AB - A new synthetic route, to prepare an alkylated indacenodithieno[3,2-b]thiophene-based nonfullerene acceptor (C8-ITIC), is reported. Compared to the reported ITIC with phenylalkyl side chains, the new acceptor C8-ITIC exhibits a reduction in the optical band gap, higher absorptivity, and an increased propensity to crystallize. Accordingly, blends with the donor polymer PBDB-T exhibit a power conversion efficiency (PCE) up to 12.4%. Further improvements in efficiency are found upon backbone fluorination of the donor polymer to afford the novel material PFBDB-T. The resulting blend with C8-ITIC shows an impressive PCE up to 13.2% as a result of the higher open-circuit voltage. Electroluminescence studies demonstrate that backbone fluorination reduces the energy loss of the blends, with PFBDB-T/C8-ITIC-based cells exhibiting a small energy loss of 0.6 eV combined with a high JSC of 19.6 mA cm−2.
KW - conjugated polymers
KW - crystal engineering
KW - nonfullerene acceptors
KW - organic solar cells
UR - http://www.scopus.com/inward/record.url?scp=85040235299&partnerID=8YFLogxK
U2 - 10.1002/adma.201705209
DO - 10.1002/adma.201705209
M3 - Article
C2 - 29315933
AN - SCOPUS:85040235299
SN - 0935-9648
VL - 30
JO - Advanced Materials
JF - Advanced Materials
IS - 8
M1 - 1705209
ER -