Robust and Sustainable Indium Anode Leading to Efficient and Stable Organic Solar Cells

The fast degradation of the charge-extraction interface at indium tin oxide (ITO) poses a significant obstacle to achieving long-term stability for organic solar cells (OSCs). Herein, a sustainable approach for recycling non-sustainable indium to construct efficient and stable OSCs and scale-up modules is developed. It is revealed that the recovered indium chloride (InCl₃ ) from indium oxide waste can be applied as an effective hole-selective interfacial layer for the ITO electrode (noted as InCl₃ -ITO anode) through simple aqueous fabrication, facilitating not only energy level alignment to photoactive blends but also mitigating parasitic absorption and charge recombination losses of the corresponding OSCs. As a result, OSCs and modules consisting of InCl₃ -ITO anodes achieve remarkable power conversion efficiencies (PCEs) of 18.92% and 15.20% (active area of 18.73 cm² ), respectively. More importantly, the InCl₃ -ITO anode can significantly extend the thermal stability of derived OSCs, with an extrapolated T₈₀ lifetime of ≈10 000 h.