title: New Wide Band Gap Donor for Efficient Fullerene-Free All-Small-Molecule Organic Solar Cells.
abstract: A new organic small molecule, DRTB-T, that incorporates a two-dimensional trialkylthienyl-substituted benzodithiophene core building block was designed and synthesized. DRTB-T has a band gap (Egopt) of 2.0 eV with a low-lying highest occupied molecular orbital (HOMO) level of -5.51 eV. Nonfullerene small-molecule solar cells consisting of DRTB-T and a nonfullerene acceptor (IC-C6IDT-IC) were constructed, and the morphology of the active layer was fine-tuned by solvent vapor annealing (SVA). The device showed a record 9.08% power conversion efficiency (PCE) with a high open-circuit voltage (Voc= 0.98 V). This is the highest PCE for a nonfullerene small-molecule organic solar cell (NFSM-OSC) reported to date. Our notable results demonstrate that the molecular design of a wide band gap (WBG) donor to create a well-matched donor-acceptor pair with a low band gap (LBG) nonfullerene small-molecule acceptor, as well as subtle morphological control, provides great potential to realize high-performance NFSM-OSCs.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Liyan
authors.initials: L
authors.lastname: Yang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|School of Chemistry and Biology Engineering, University of Science and Technology Beijing , Beijing 100083, China.
authors.forename: Shaoqing
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Chang
authors.identifier: 0000-0002-9804-5455
authors.initials: C
authors.lastname: He
authors.affiliation: University of Chinese Academy of Sciences , Beijing 100049, China.|Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology , Beijing 100190, China.
authors.forename: Jianqi
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Huifeng
authors.initials: H
authors.lastname: Yao
authors.affiliation: Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology , Beijing 100190, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Wenchao
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Hou