Formation of Metal Cation/Oxidized Pyridine Complexes‐Based Bifunctional Interfacial Layer for Fabrication of Highly Efficient and Reproducible Perovskite Solar Cells. Issue 7 (10th April 2022)

• Record Type: Journal Article
• Authors: Oh, Heeyoon; Kang, Gumin; Park, Minwoo
• Is Part Of: Solar RRL. Volume 6:Issue 7(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-04-10
• Subjects: complexation -- interfacial passivation -- perovskite solar cells poly(4-vinylpyridine) -- UV–ozone treatments; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202200163
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Interfacial engineering of perovskite solar cells (PSCs) has been a core process for enhancing their power conversion efficiencies (PCEs) and environmental stability. Particularly, polymeric passivation of a metal oxide–electron transport layer (ETL) not only leads to a reduction in its surface defects but also improves the morphology of perovskite. However, the dissolution of the passivation layers by dimethylformamide (DMF) in a perovskite solution can cause a significant drop in the PCE and reproducibility of devices. Herein, oxidized poly(4‐vinylpyridine) (O‐P4VP) is used as a bifunctional passivation layer. The O‐P4VP layers are completely insoluble in DMF, which accompanies the highly reproducible deposition of perovskites without damaging the layers. Furthermore, based on metal–pyridine complexation, oxygen vacancies on the surface of the SnO2 ETLs are passivated with the O‐P4VP layers, and the perovskite grains become enlarged by the controlled nucleation and growth rate. The synergetic effects of interfacial passivation present deeper energy levels of the ETL and a prolonged photoluminescence lifetime of the perovskites. The resulting PCE jumps from 19.05% to 21.11% with respect to the pristine device, and the value is retained for 720 h under 1 sun illumination. Abstract : Oxidized poly(4‐vinylpyridine) (O‐P4VP) as an interfacial passivation layer of perovskite solar cells improves power conversion efficiencies to 21.11% and environmental stability. Based on metal–pyridine complexation, defect passivation of SnO2 and increase in the grain size of perovskite are achieved simultaneously. The insoluble passivation layer in perovskite solutions also contributes to the fabrication of highly reproducible devices.