[25p-E206-1~9] 12.5 Organic solar cells

▲ [25p-E206-8] Naphthobisthiadiazole-triphenylenobisthiadiazole Random Copolymers for Non-Fullerene Solar Cells

〇Lihui Chou¹, Tsubasa Mikie¹, Masahiko Saito¹, Fengkun Chen², Kyohei Nakano², Keisuke Tajima², Itaru Osaka¹ (1.Hiroshima Univ., 2.RIKEN CEMS)

Keywords:non-fullerene solar cell, semiconducting polymer, random copolymer

Semiconducting polymers have attracted great attention in the field of organic electronics because of the good optoelectronic properties and solution processability. We have reported that a naphthobisthiadiazole-based semiconducting polymer (PNTz4T) exhibited a relatively small bandgap and highly crystalline structure, which led to high performance in fullerene-based solar cells. However, PNTz4T had relatively low solubility, which hampered solution processability, due to its high crystallinity. In this study, a series of NTz-based random copolymers incorporating small amount of triphenylenobisthiadiazole with different alkyl sidechain were designed and synthesized. We expected that introduction of TPTz having a V-shaped structure would increase the solubility of the polymer while preserving the crystallinity. The impact of introducing the TPTz core unit on the energetics, film structures, and photovoltaic performances in the solar cells are investigated.