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Published on: May 29, 2018
Precisely Manipulating Molecular Packing via Tuning Alkyl Side-Chain Topology Enabling High-Performance Nonfused-Ring
Ziyang Han1, Cai'e Zhang1, Tengfei He2
1College of Materials Science and Opto-Electronic Technology, Center of Materials Science and Optoelectronics Engineering, CAS Center for Excellence in Topological Quantum Computation, CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, China.
Abstract:
In the development of high-performance organic solar cells (OSCs), the self-organization of organic semiconductors plays a crucial role. This study focuses on the precisely manipulation of molecular assemble via tuning alkyl side-chain topology in a series of low-cost nonfused-ring electron acceptors (NFREAs). Among the three NFREAs investigated, DPA-4, which possesses an asymmetric alkyl side-chain length, exhibits a tight packing in the crystal and high crystallinity in the film, contributing to improved electron mobility and favorable film morphology for DPA-4. As a result, the OSC device based on DPA-4 achieves an excellent power conversion efficiency of 16.67 %, ranking among the highest efficiencies for NFREA-based OSCs.
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