Although the combination of wide band gap polymer donors and narrow band gap small-molecule acceptors achieved state-of-the-art performance as bulk heterojunction (BHJ) active layers for organic solar cells, there have been only several of the wide band gap polymers that actually realized high-efficiency devices over >10%. Herein, we developed high-efficiency, low-energy-loss fullerene-free organic solar cells using a weakly crystalline wide band gap polymer donor, PBDTTPD-HT, and a nonfullerene small-molecule acceptor, ITIC. The excessive intermolecular stacking of ITIC is efficiently suppressed by the miscibility with PBDTTPD-HT, which led to a well-balanced nanomorphology in the PBDTTPD-HT/ITIC BHJ active films. The favorable optical, electronic, and energetic properties of PBDTTPD-HT with respect to ITIC achieved panchromatic photon-to-current conversion with a remarkably low energy loss (0.59 eV).
Bibliographical noteFunding Information:
The authors gratefully acknowledge the support from the New and Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP); the granted financial resources from the Ministry of Trade, Industry and Energy, Republic of Korea (no. 20163030013960); the Technology Development Program to Solve Climate Changes of the National Research Foundation (NRF) funded by the Ministry of Science, ICT and Future Planning (NRF-2016M1A2A2940912); the National Research Foundation (NRF) grant funded by the Korean Government (2016R1A5A1012966, 2017R1A2B2009178, and 2017R1C1B2010694); and the Global Scholarship Program for Foreign Graduate Students at Kookmin University in Korea.
All Science Journal Classification (ASJC) codes
- Materials Science(all)