Understanding mechanisms and applications of dilute donor non-fullerene organic solar cells

The composition dependence of OSCs based on PM6 and Y6 was studied. Surprisingly, a power conversion efficiency (PCE) over 10% was achieved in the OSCs with 10 wt % PM6. Study indicates that 10 wt % PM6 is sufficient to provide efficient hole transport.[1] Furthermore, vacuum free solution-processed semitransparent OSCs (ST-OSCs) containing 10% - 45% PM6 were studied by employing PEDOT:PSS as an electrode. The light utilization efficiency (LUE) of 2.72% (defined as a product of PCE and AVT) was realized in ST-OSCs with 20 wt % PM6, which is among the best reported values for solution-processed ST-OSCs. This work provides a straightforward approach to achieve high LUE solution-processed ST-OSCs by combining small fraction visible-absorbing donors with more near-infrared acceptors, which opens applications of ST-OSCs as BIPVs.