Crystallization and Defect Regulation in Sn–Pb Perovskite Solar Cells via Optimized Anti‐Solvent Passivation Strategy. Issue 10 (25th August 2022)

• Record Type: Journal Article
• Authors: Pan, Lu; Li, Hui; Chang, Bohong; Yin, Longwei
• Is Part Of: Solar RRL. Volume 6:Issue 10(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-25
• Subjects: anti-solvents -- MACl -- perovskites -- Sn–Pb mixed perovskites -- solar cells; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202200398
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Low bandgap tin–lead halide perovskite (PVSK) presents promising opportunities for high‐performance solar cells. However, the randomly crystallized Sn–Pb PVSK with a tin‐rich surface is easily oxidized, leading to high‐level p‐type doping, which hinders the performance enhancement of the solar cell devices. Herein, an efficient anti‐solvent passivation strategy to regulate defect, crystallization, and energy conversion performance based on anti‐solvents composed of chlorobenzene, isopropanol, and methylammonium chloride (MACl) is proposed. It is shown that the Sn–Pb PVSK film gets more moderate and order, with less PbI2 and more α‐phase PVSK formed. Furthermore, it is revealed that the surface of the as‐processed film is Pb‐rich, demonstrating a decrease in the surface p‐type concentration, which is more suitable for the photoelectric conversion enhancement of the inverting device. Finally, the MACl‐assisted post‐treated Sn–Pb PVSK invert solar cells exhibit a high current density of 26.49 mA cm −2 with a open‐circuit voltage of 0.70 V and a power conversion efficiency of 16.05%. The modified anti‐solvent process fuses the advantage of additive and anti‐solvent engineering for growing highly crystallized hybrid tin‐lead halide PVSK for photovoltaic devices. Abstract : Methylammonium chloride is added in chlorobenzene and isopropanol co‐anti‐solvent to post‐treat the Sn–Pb mixed perovskite (PVSK), which induces more Sn‐rich PVSK grains formed on the bottom, and more Pb‐rich crystal particles on the top surface. The PVSK surface is eventually terminated with a Pb‐rich shell, leading to the PVSK more humidity‐stable and more suitable for photoelectric conversion.