A Non-fullerene Acceptor with Enhanced Intermolecular pi-Core Interaction for High-Performance Organic Solar Cells

Top Cited Papers
Publisher Website
Google Scholar
Abstract
Understanding the molecular structure and self-assembly of thiadiazole-derived non-fullerene acceptors (NFAs) is very critical for elucidating the origin of their extraordinary charge generation and transport properties that enable high power conversion efficiencies to be achieved in these systems. A comprehensive crystallographic study on a state-of-the-art NFA, Y6, and its selenium analog, CH1007, has been conducted which revealed that the face-to-face pi-core interaction induced by benzo[2,1,3]thiadiazole S-N-containing moieties plays a significant role in governing the molecular geometries and unique packing of Y6 and CH1007 to ensure their superior charge-transport properties. Moreover, benefitting from the red-shifted optical absorption via selenium substitution, photovoltaic devices based on a PM6:CH1007:PC71BM ternary blend delivered an exceptionally high short-circuit current of 27.48 mA/cm(2) and a power conversion efficiency of 17.08%.
Funding Information
  • Innovation and Technology Fund (GHP/021/18SZ, ITS/497/18FP)
  • Office of Naval Research (N00014-20-1-2191)
  • City University of Hong Kong (9380086, 9610421)
  • Guangdong Province (2019B030302007)
  • Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials (2019B121205002)