Multifunctional Molecule‐Modified SnO2–Perovskite Interface for Efficient Planar Perovskite Solar Cells. Issue 14 (23rd March 2022)

• Record Type: Journal Article
• Authors: Xin, Xu; Yang, Jiabao; Pu, Xingyu; Li, Yuke; Wang, Tong; Chen, Hui; Cao, Qi; Zhang, Yixin; Tojiboyev, Ilhom; Salari, Hadi; Ye, Fei; Li, Xuanhua
• Is Part Of: Advanced materials interfaces. Volume 9:Issue 14(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-23
• Subjects: 4‐fluoro‐phenylalanine -- electron transport layers -- perovskite/SnO 2 interface modification -- perovskite solar cells -- tin oxide; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.202200102
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: The electron transport layer (ETL) is one of the determinants for the performance improvement of perovskite solar cells (PSCs). Here, a multifunctional molecule named 4‐fluoro‐phenylalanine (4‐F‐Phe) to modify the surface of tin oxide (SnO2 ) ETL is introduced as a novel interfacial layer for high‐efficiency PSCs. The modified SnO2 ETLs exhibit an elevated Fermi level, increasing the carrier extraction and suppressing the interfacial recombination. In addition, the various functional groups of the 4‐F‐Phe realize strong interfacial interactions with both the bottom SnO2 ETLs and the top perovskite, which reduces trap state density significantly to promote the interfacial charge transport. As a result, power conversion efficiency (PCE) for the 4‐F‐Phe optimized device reaches 21.91%. Most importantly, the 4‐F‐Phe optimized device without encapsulation maintains 91% of its initial PCE after 2000 h at 25 °C with a humidity of 50 ± 5%, and 90% of the initial PCE after 1000 h at 80 °C in N2 . In addition, the encapsulated devices maintain 94% of their initial efficiency under continuous 1 sun illumination for 1000 h when tracking the maximum power point at 45 °C. This work provides a new strategy of modifying ETL to simultaneously improve the efficiency and stability of PSCs. Abstract : A multifunctional molecule named 4‐fluoro‐phenylalanine (4‐F‐Phe) is introduced as a novel interfacial layer to modify the surface of SnO2 electron transport layer and achieve 21.91% high‐efficiency perovskite solar cell. The optimized device displays excellent long‐term stability.