10.1021/cm5002303.s002 Julien Warnan Julien Warnan Clément Cabanetos Clément Cabanetos Romain Bude Romain Bude Abdulrahman El Labban Abdulrahman El Labban Liang Li Liang Li Pierre M. Beaujuge Pierre M. Beaujuge Electron-Deficient <i>N</i>‑Alkyloyl Derivatives of Thieno[3,4‑<i>c</i>]pyrrole-4,6-dione Yield Efficient Polymer Solar Cells with Open-Circuit Voltages > 1 V American Chemical Society 2014 polymer LUMO 0.9 V TPD material properties power conversion efficiencies ring substituents BDT motifs HOMO levels BHJ device VOC Recent work PBDTTPD FF 1.1 V 1 V PCBM acceptors device VOC side chains PCE polymer donors 2014-05-13 00:00:00 Dataset https://acs.figshare.com/articles/dataset/Electron_Deficient_i_N_i_Alkyloyl_Derivatives_of_Thieno_3_4_i_c_i_pyrrole_4_6_dione_Yield_Efficient_Polymer_Solar_Cells_with_Open_Circuit_Voltages_1_V/2297557 Poly­(benzo­[1,2-b:4,5-b′]­dithiophene–thieno­[3,4-<i>c</i>]­pyrrole-4,6-dione) (PBDTTPD) polymer donors yield some of the highest open-circuit voltages (<i>V</i><sub>OC</sub>, ca. 0.9 V) and fill factors (FF, ca. 70%) in conventional bulk-heterojunction (BHJ) solar cells with PCBM acceptors. Recent work has shown that the incorporation of ring substituents into the side chains of the BDT motifs in PBDTTPD can induce subtle variations in material properties, resulting in an increase of the BHJ device <i>V</i><sub>OC</sub> to ∼1 V. In this contribution, we report on the synthesis of <i>N</i>-alkyloyl-substituted TPD motifs (TPD­(CO)) and show that the electron-deficient motifs can further lower both the polymer LUMO and HOMO levels, yielding device <i>V</i><sub>OC</sub> > 1 V (up to ca. 1.1 V) in BHJ solar cells with PCBM. Despite the high <i>V</i><sub>OC</sub> achieved (i.e., low polymer HOMO), BHJ devices cast from TPD­(CO)-based polymer donors can reach power conversion efficiencies (PCEs) of up to 6.7%, making these promising systems for use in the high-band-gap cell of tandem solar cells.