Enhancing Long-Term Thermal Stability of Non-Fullerene Organic Solar Cells Using Self-Assembly Amphiphilic Dendritic Block Copolymer Interlayers

摘要

Herein, interfacial engineering is demonstrated to improve the thermal stability of non-fullerene bulk-heterojunction (BHJ) OPVs to a practical level. An amphiphilic dendritic block copolymer (DBC) is developed through a facile coupling method and employed as the surface modifier of ZnO electron-transporting layer in inverted OPVs. Besides showing distinct self-assembly behavior, the synthesized DBC possesses high compatibility with plasmonic gold nanoparticles (NPs) due to the constituent malonamide and ethylene oxide units. The hybrid DBC@AuNPs interlayer is shown to improve device's performance from 14.0% to 15.4% because it enables better energy-level alignment and improves interfacial compatibility at the ZnO/BHJ interface. Moreover, the DBC@AuNPs interlayer not only improves the interfacial thermal stability at the ZnO/BHJ interface but also endows a more ideal BHJ morphology with an enhanced thermal robustness. The derived device reserves 77% of initial PCE after thermal aging at 65 degrees C for 3000 h and yields an extendedT(80)lifetime of 1100 h when stored at a constant thermal condition at 65 degrees C, outperforming the control device. Finally, the device is evaluated to possess aT(80)lifetime of over 1.79 years at room temperature (298 K) when stored in an inert condition, showing great potential for commercialization.