High-Throughput Screening of Organic Solar Cells Based on PTQ10:NFA to Determine the Best Compromise Between Efficiency and Stability

High power conversion efficiency (PCE) and stability are essential for the industrial viability of organic photovoltaic (OPV). The optimization of device PCE and stability is a multi-parameter complex system. High-throughput screening offers tremendous opportunities to accelerate the discovery of optimal material composition and structure of efficient and stable organic solar cells.<br/><br/>In this work, we present the stability of organic solar cells based on PTQ10 with different acceptors. First, we evaluate the impact of the molecular weigth (MW) of the PTQ10 donor polymer blended with three differente non-fullerene acceptors (NFAs) (ie. IDIC, Y6 and Y12) on the performance of organic solar cells. By increasing the MW from 10 to 147 kDa, the efficiency improves by one order of magnitude, from around 2% up to 12%. The devices with higher molecular weights also show better thermal stability. We also characterized the active layer materials by photoluminicence, Grazing-Incidence Wide-Angle X-ray Scattering (GIWAXS) and charge carrier mobility.<br/><br/>Moreover, we explore by combinatorial screening the dependence of the stability with the active layer thickness following ISOS protocols, in order to determine if the optimal thickness for power conversion efficiency matches the thickness of the most stable devices.<br/><br/>As a result, we report stable and promising systems of organic solar cells for industrialisation of low cost organic photovoltaics.