Details

Autor(en) / Beteiligte

• Cao, Fong-Yi
• Hsu, Jhih-Yang
• Hung, Kai-En
• Cheng, Yen-Ju

Titel

Synthesis of naphtho[1,2-d:5,6-d']bis([1,2,3]triazole)-based wide-bandgap alternating copolymers for polymer solar cells and field-effect transistors

Ist Teil von

• Polymer journal, 2023-04, Vol.55 (4), p.417-426

Ort / Verlag

Tokyo: Nature Publishing Group

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The development of wide bandgap p-type conjugated polymers to pair with low bandgap nonfullerene n-type acceptors (NFAs) has emerged as an important topic in polymer solar cells. Naphtho[1,2-d:5,6-d’]bis([1,2,3]triazole (NTz), in which the central nitrogen bears an aliphatic side chain, can serve as a mild electron acceptor to generate wide bandgap p-type conjugated polymers. To this end, we synthesized two donor-acceptor alternating copolymers, PBDTNTz1 and PBDTNTz2, based on naphthobistriazole (NTz) as the acceptor and benzodithiophene (BDT) as the donor. The two polymers had optical bandgaps of ca. 1.9 eV with absorption spectra complementary to that of the typical nonfullerene n-type acceptor ITIC. Side-chain engineering was implemented by introducing different combinations of alkyl groups on the BDT and NTz units in PBDTNTz1 and PBDTNTz2. According to theoretical calculations, PBDTNTz1 has higher backbone coplanarity with a face-on π-π stacking orientation. Consequently, a device with the PBDTNTz1:ITIC combination delivered a high PCE of 7.37% with a Voc of 0.94 V, a Jsc of 14.04 mA/cm2 and an FF of 55.8%. In addition, organic field-effect transistors (OFETs) using PBDTNTz1 and PBDTNTz2 exhibited hole mobilities of 2.2 × 10−2 cm2V−1s−1 and 5.0 × 10−2 cm2V−1s−1 with on/off ratios of 1 × 104 and 9 × 102, respectively.PBDTNTz1 and PBDTNTz2 combining naphtho[1,2-d:5,6-d’]bis([1,2,3]triazole (NTz) and benzo[1,2-b:4,5-b’]dithiophene (BDT) were successfully synthesized as wide-band gap polymers for nonfullerene acceptor polymer solar cells. Bulk heterojunction solar cells with inverted structures using PBDTNTz2:ITIC showed a 2.39% power conversion efficiency. The device utilizing PBDTNTz1:ITIC presented a 7.37% PCE with a high Voc of 0.94 V, an FF of 55.8, and a Jsc of 14.04 mA/cm2. OFETs using PBDTNTz1 and PBDTNTz2 showed hole mobilities of 2.2 × 10−2 cm2V−1s−1 and 5.0 × 10−2 cm2V−1s−1 with current on/off ratios of 1 × 104 and 9 × 102, respectively.