Perovskite solar cells based on hole-transporting conjugated polymers by direct arylation polycondensation


Direct arylation polycondensation (DArP) is an emerging synthetic method of producing conjugated polymers in an environmentally benign and cost-effective manner. We now report the synthesis of hole-transporting conjugated polymers, namely, DPP-OMe (Mn= 7.9 kg/mol) and DPP-F (Mn = 12.6 kg/mol), under microwave-assisted DArP conditions. These two polymers and the previously synthesized 3,6-Cbz-EDOT were evaluated as hole-transporting materials in mesoscopic perovskite solar cells. 3,6-Cbz-EDOT synthesized by DArP exhibited higher hole mobility and better photovoltaic properties than that synthesized by the Stille polycondensation. Moreover, chemical dopants improved the short-circuit current density (Jsc) and fill factor.

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This work was supported by the Heiwa Nakajima Foundation, the Ogasawara Foundation for the Promotion of Science and Technology, the Yazaki Memorial Foundation for Science and Technology, the SEI Group CRS Foundation, and the Support for Tokyotech Advanced Researcher.

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Correspondence to Tsuyoshi Michinobu.

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Hole-transporting conjugated polymers synthesized by direct arylation polycondensation show higher hole mobilities and better photovoltaic performances of the perovskite solar cells than those synthesized by the conventional Stille coupling polycondensation.

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Li, W., Mori, T. & Michinobu, T. Perovskite solar cells based on hole-transporting conjugated polymers by direct arylation polycondensation. MRS Communications 8, 1244–1253 (2018).

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