| Autor: |
Wang CH; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Busireddy MR; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Huang SC; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Nie H; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Liu YS; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Lai BY; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Meng LH; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Chuang WT; National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu 30073, Taiwan., Scharber MC; Linz Institute of Organic Solar Cells (LIOS), Institute of Physical Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, Linz 4040, Austria., Chen JT; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan., Hsu CS; Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan.; Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, 1001 University Rood, Hsinchu 300093, Taiwan. |
| Abstrakt: |
Alkoxy side chain engineering on the β-position of the thienothiophene units of Y6 derivatives plays a vital role in improving photovoltaic performances with simultaneously increasing open-circuit voltage ( V oc ) and fill factor (FF). In this work, we prepared a series of asymmetric non-fullerene acceptors (NFAs) by introducing alkoxy side chains and phenoxy groups on the state-of-the-art Y6-derivative BTP-BO-4F. For the comparison, 2O-BO-4F with a symmetric alkoxy side chain on the outer thiophene units and BTP-PBO-4F with an asymmetric N -attached phenoxy alkyl chain on the pyrrole ring are synthesized from BTP-BO-4F. Thereafter, we construct four asymmetric NFAs by introducing different lengths of linear/branched alkoxy chains on the β-position of the thienothiophene units of BTP-PBO-4F. The resulting NFAs, named L10-PBO, L12-PBO, B12-PBO, and B16-PBO (L = linear and B = branched alkoxy side chains), are collectively called OR-PBO-series. Unexpectedly, all OR-PBO NFAs exhibit strong edge-on molecular packing and weaker π-π interactions in the film state, which diminish the charge transfer in organic solar cell (OSC) devices. As a consequence, the optimal devices of OR-PBO-based binary blends show poor photovoltaic performances [power conversion efficiency (PCE) = 6.52-9.62%] in comparison with 2O-BO-4F (PCE = 12.42%) and BTP-PBO-4F (PCE = 15.30%) reference blends. Nevertheless, the OR-PBO-based binary devices show a higher V oc and smaller V loss . Especially, B12-PBO- and B16-PBO-based devices achieve V oc over 1.00 V, which is the highest value of Y-series OSC devices to the best of our knowledge. Therefore, by utilizing higher V oc of OR-PBO binary blends, B12-PBO and B16-PBO are incorporated into the PM6:BTP-PBO-4F-based binary blend and fabricated ternary devices. As a result, the PM6:BTP-PBO-4F:B12-PBO ternary device delivers the best PCE of 15.60% with an increasing V oc and FF concurrently. |
