Additive and Interface Engineering via Crosslinked 3D Polymer Network for Efficient and Stable Perovskite Solar Cells

In this study, a facile and promising strategy is presented to enhance the performance and stability of perovskite solar cells (PeSC) by incorporating tri(ethylene glycol) divinyl ether (TEGDVE) as the additive and dopant for perovskite active layer and amine‐functionalized perylene diimide (PDIN) cathode interfacial layer, respectively. The results indicate that the electron‐donating oxygen atoms of TEGDVE can interact with undercoordinated Pb 2+ via the formation of coordination bond, which synchronously passivates the defects within perovskite film and manipulates the crystallization kinetics. Additionally, the vinyl functional groups on TEGDVE can undergo thermal cross‐linking reaction and form three‐dimensional polymer network, enabling perovskite film to possess good optoelectronic properties and enhanced moisture stability. In addition, the incorporation of TEGDVE can induce n‐doping of PDIN due to its adequate electron donation capability offered by oxygen atoms. With these appealing features, the resulting device delivers not only high power conversion efficiency up to 20.90% but also satisfied ambient stability, greatly outperforming those of the PeSC without TEGDVE. This work provides a new avenue to improve the efficiency and stability of PeSC based on a facile strategy. The findings present a significant step towards the practical applications of this emerging technology.