Recent progress and perspective in solution-processed Interfacial materials for efficient and stable polymer and organometal perovskite solar cells

In this review, we summarize the latest developments in solution-processed interfacial layers that have contributed to the significantly improved performance of polymer and perovskite solar cells (PSCs and PVSCs). The solution-processed interfacial materials, including organic electrolytes, organic-inorganic hybrids, graphene oxides (GOs), transition metal oxides (TMOs), and self-assembled functional materials, along with their integration into efficient PSCs, polymer tandem cells (PTCs), and the emerging perovskite solar cells (PVSCs) are discussed. Regarding the rapid progress of PSCs and PVSCs, strategies and perspectives of further improving solution-processed interfacial materials are also discussed to help readers understand the challenges and opportunities in transitioning from scientific curiosity into technology translation for realizing low-cost, printable, and high-efficiency flexible solar cells to address the scalability issues facing solar energy.