122nd General Meeting of the KCS

Type Oral Presentation
Area Oral Presentation for Young Polymer Scientists
Room No. Room 325C+D
Time THU 09:20-:
Code POLY.O-3
Subject Green-solvent processable semiconducting polymers applicable in additive-free perovskite and polymer solar cells: molecular weights,photovoltaic performance, and thermal stability
Authors Junwoo Lee, Guan-Woo Kim, Taewan Kim, Taiho Park*
Department of Chemical Engineering, Pohang University of Science and Technology, Korea
Abstract In this study, we demonstrated a novel approach to increase solubility in green solvent (2-methylanisole; food additives) and the effects of the molecular weight(MW) of a green-solvent processable semiconducting polymer (asy-PBTBDT) on its photovoltaic performance and device thermal stability in green processed devices for the first time. The asy-PBTBDT witha high MW(132 kDa) had the highest hole mobility values (4.91x10^ -3 cm^2 V -1 s -1without dopants and 5.77x10 ^ -3 cm^2 V -1 s -1 with dopants) as a resultof increase in the p–p stacking along with MW as compared to low-MW asy-PBTBDTs (27 and 8 kDa). The high-MW asy-PBTBDT witha high mh achieved the best power conversion efficiencies of 18.2%and 20.0% for the undoped and doped states in PerSCs, respectively,and 5.7% in PSCs in green processed devices. Furthermore, the glasstransition temperature increased with an increase in MW; this indicatedan effective decrease in heat-induced morphological degradationin the photovoltaic devices. In addition, an increase in thechain density along withMW led to good robustness against humidity and oxygen.
E-mail junwoolee@postech.ac.kr