High-Performance Semitransparent Organic Solar Cells Enabled by Improved Charge Transport and Optical Engineering of Ternary Blend Active Layer

Semitransparent organic solar cells (STOSCs) make the industrialization of power-generating windows a reality with promising average visible transmittance (AVT) and rapidly increased power conversion efficiencies (PCEs). To achieve the ultimate goal, improving the efficiency of STOSCs without degrading the transparency in visible range is critical. Herein, a nonfused ring acceptor (BDC-4F-C8) by alkyl chain engineering is used as third component for ternary blend active layer to enhance the electrical and optical properties of STOSCs. With optimizing the proportion of third component, STOSCs with ternary active layer exhibit improved open-circuit voltage, short-circuit current, and fill factor, which leads to the best PCE of 13.19% with AVT of 24.56%, while the PCE of opaque one is 17.02%. This work presents an effective strategy to achieve high-performance ternary STOSCs with high AVT employing a low-cost nonfused ring electron acceptor material, and manifests how the third component affects the optical features of a ternary active layer to achieve efficient semitransparent devices.