Molecular helices as electron acceptors in high-performance bulk heterojunction solar cells

Despite numerous organic semiconducting materials synthesized for organic photovoltaics in the past decade, fullerenes are widely used as electron acceptors in highly efficient bulk-heterojunction solar cells. None of the non-fullerene bulk heterojunction solar cells have achieved efficiencies as high as fullerene-based solar cells. Design principles for fullerene-free acceptors remain unclear in the field. Here we report examples of helical molecular semiconductors as electron acceptors that are on par with fullerene derivatives in efficient solar cells. We achieved an 8.3% power conversion efficiency in a solar cell, which is a record high for non-fullerene bulk heterojunctions. Femtosecond transient…

• NS
  National Science Foundation

  Awards: 1321405, 0936384, DMR 1321405, 1332208, DMR-1332208, DMR-0936384, DE-SC0012704
• UD
  U.S. Department of Energy

  Awards: DMR-1332208, DE-FG02-01ER15264, SC0012704, FG02-01ER15264, DE-FG02-, DE-FG02
• NI
  National Institutes of Health

  Awards: DMR-1332208, DMR-0936384
• OO
  Office of Science

  Awards: SC0012704, DE-SC0012704
• ND
  National Defense Science and Engineering Graduate

  Awards: 32 CFR 168a, CFR 168a
• NI
  National Institute of General Medical Sciences

  Awards: DMR-0936384, DMR-1332208
• DO
  Division of Materials Research

  Awards: DMR-1332208, 0936384, DMR-0936384, DMR 1321405, 1332208
• BE
  Basic Energy Sciences

  Awards: DE-SC0012704, DE-FG02, SC0012704, DE-FG02-01ER15264
• BN
  Brookhaven National Laboratory

  Award: SC0012704