120th General Meeting of the KCS

Type Symposium
Area Special Symposium by Leading Mid-career Polymer Scientists
Room No. Room 302+303
Time THU 13:55-:
Code POLY2-2
Subject A novel strategy in design of polymeric hole transporting materials for green processable, dopant-free perovskite solar cells
Authors Taiho Park
Department of Chemical Engineering, Pohang University of Science and Technology, Korea
Abstract Spiro-OMeTAD as hole transporting material (HTM) has been widely employed up to PCE = 22.1 %, but it is only processed in chlorinated or harmful solvents such as chlorobenzene (CB), dichlorobenzene (DCB), or toluene, despite of its low molecular weight relative to polymeric HTMs. Therefore, it is necessity to replace it to green solvent processable HTM. Here, we report a green solvent processable, polymeric HTM consisting of benzodithiazole and benzo[1,2-b:4,5:b’]dithiophene. We design a novel D (e-donor) – A (e-acceptor) type conducting polymer to obtain its proper highest occupied energy level (HOMO) easily and to achieve its high hole mobility as we demonstrated, allowing effective hole extraction from perovskites to HTM and then hole transportation through HTM without Li-TFSI and t-BP, respectively. The resulting novel polymeric HTM is not only soluble in the various halogenated or harmful solvents but also highly soluble in a green solvent. In this talk, I will present a design strategy for a green solvent processable HTM and why it exhibits a highly stable device with a highest PCE in the absence of the dopants. [References] 1) YS Kwon, J Lim, H-J Yun, Y-H Kim, T Park, Energy Environ. Sci. 2014, 7, 1454. 2) G-W Kim, J Kim, G-Y Lee, G Kang, J Lee, T Park, Adv. Energy Mater. 2015, 5, 1500471. 3) G-W Kim, DV Shinde, T Park, RSC Advances 2015, 5, 99356. 4) G-W Kim, G Kang, J Kim, G-Y Lee, H Kim, L Pyeon, J Lee, T Park, Energy Environ. Sci. 2016, 9, 2326. 5) G-W Kim, G Kang, MM Byranvand, G-Y Lee, T Park, ACS Appl. Mater. & Inter. 2017, 9, 27720. 6) G-W Kim, J Lee, G Kang, T Kim, T Park, Adv. Energy Mater. 2017, accepted. 7) J Lee, MM Byranvand, G Kang, SY Son, S Song, G-W Kim, T Park, J. Am. Chem. Soc. 2017, accepted.
E-mail taihopark@postech.ac.kr