Presentation Information
[10a-PB1-21]Dual Interfacial Engineering through Bifunctional Multidentate Linkers for Efficient and Stable Photovoltaics
〇MingChung Wu1, HongYi Lin1, KaiChi Hsiao1, TingHan Lin1, JiaMao Chang1, WeiChen Chu1, WeiHao Chiu1, KunMu Lee1 (1.Chang Gung Univ.)
Keywords:
perovskite solar cell,multidentate molecule,buried interface
Regulating the buried layer crystallization at the electron transport layer interface is a critical yet rarely explored aspect of fabricating high-quality perovskites. Here, we present an innovative interfacial engineering concept employing 2-aminoethylphosphonic acid (APA) to reconcile both mechanical and electronic mismatches at the SnO2/perovskite interface. APA acts as a bifunctional agent: its flexible molecular backbone functions as a geometric tuner that releases interfacial compressive stress, reducing strain by more than 20%, while its phosphonate and amino headgroups serve as electronic passivators. These functional groups directionally anchor onto the $ SnO2 and perovskite terminal facets via their respective electron-withdrawing and electron-donating properties. This targeted alignment and stress mitigation suppress electronic defects, successfully widening the quasi-Fermi level splitting from the perovskite to the SnO2 layer. As a result, the optimized device delivers a champion power conversion efficiency of 22.92% and sustains over 1,500 hours of operation in air without encapsulation. This strategy underscores the importance of balancing molecular orientation and mechanical stress relief for durable, high-efficiency perovskite solar cells.