Improving Light Stability of Nonfullerene Acceptor Inverted Organic Solar Cell by Incorporating a Mixed Nanocomposite Metal Oxide Electron Transporting Layer

We present significant light stability enhancement of nonfullerene acceptor inverted organic photovoltaics by incorporating a mixed nanocomposite metal oxide electron transporting layer. Using an appropriate mixture of ZnO:SnO₂ nanoparticles as an electron transporting layer in a PBDB-TF-T1 (T1):IT4F based organic solar cell device mitigates light induced photodegradation by lowering the defect formation at the active layer interface. We propose that the mixed metal oxide ETL act as hole scavengers that reduces the photocatalytic reaction of its surface. The optimized nanocomposite mixture of ZnO:SnO₂ 10:90 (%V) provides higher light stability (ISOS-L2 protocol), prolonging the inverted OSCs lifetime (80% of the initial PCE, T80) by ∼16.5 times compared to the commonly used pristine ZnO electron transporting layer.