121st General Meeting of the KCS

Type Oral Presentation
Area Oral Presentation for Young Polymer Scientists
Room No. Room 301
Time THU 09:30-:
Code POLY.O-3
Subject Improving the Photovoltaic Performances and Stability of Inverted Flexible Perovskite Solar Cells Employing a Novel NDI-based Polymeric Electron Transporting Layer
Authors HONG IL KIM, Minjun Kim1, Taewan Kim, Taiho Park*
Department of Chemical Engineering, Pohang University of Science and Technology, Korea
1Chemical engineering, Pohang University of Science and Technology, Korea
Abstract A new naphthalene diimide (NDI)-based polymer with strong electron withdrawing dicyanothiophene (P(NDI2DT-TTCN)) is developed as the electron transport layer (ETL) in place of the fullerene-based ETL in inverted perovskite solar cells (Pero-SCs). A combination of characterization techniques, including atomic force microscopy, scanning electron microscopy, grazing-incidence wide-angle X-ray scattering, near-edge X-ray absorption fine-structure spectroscopy, space-charge-limited current, electrochemical impedance spectroscopy, photoluminescence (PL), and time-resolved PL decay, is used to demonstrate the interface phenomena between perovskite and P(NDI2DT-TTCN) or PCBM. It is found that P(NDI2DT-TTCN) not only improves the electron extraction ability but also could prevent ambient condition interference by forming a hydrophobic ETL surface. In addition, P(NDI2DT-TTCN) has excellent mechanical stability compared to PCBM in flexible Pero-SCs. With these improved functionalities, the performance of devices based on P(NDI2DT-TTCN) significantly outperform those based on PCBM from 14.3% to 17.0%, which is the highest photovoltaic performance with negligible hysteresis in the field of polymeric ETLs.
E-mail hongilkim@postech.ac.kr