Surface Passivation with Diaminopropane Dihydroiodide for p‐i‐n Perovskite Solar Cells with Over 25% Efficiency

• Published in: Advanced functional materials 2024-03, Vol.34 (12), p.n/a
• Main Authors: Lan, Zhong‐Rui, Wang, Yu‐Duan, Shao, Jiang‐Yang, Ma, Dian‐Xue, Liu, Zhenghao, Li, Dongmei, Hou, Yi, Yao, Jiannian, Zhong, Yu‐Wu
• Format: Article
• Language: English
• Subjects: Carrier transport; charge recombination; Current carriers; Defect annealing; Electron transport; inverted perovskite solar cells; organic ammonium salts; passivating defects; Passivity; Perovskites; Photovoltaic cells; Radiative recombination; rubidium‐cesium perovskite; Solar cells; Storage stability; Surface defects
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202312426

At present, one of the major factors limiting the further improvement of inverted (p‐i‐n) perovskite solar cells (PSCs) is trap‐assisted non‐radiative recombination at the perovskite/electron transporting layer (ETL) interface. Surface passivation with organic ammonium salt is a powerful strategy to improve the performance of PSCs. Herein, an effective method by using propylamine hydroiodide (PAI) and 1,3‐diaminopropane dihydroiodide (PDADI) is reported to modify the perovskite/ETL interface. These two ammonium salts do not form new perovskite but directly passivate the defects on the perovskite surface after annealing. The results show that the PDADI‐modified perovskite films possess a lower surface defect density and less non‐radiative recombination as well as improved charge carrier transport. Based on this strategy, the PDADI‐modified p‐i‐n PSCs deliver an impressive efficiency of 25.09% (certified 24.58%) with an open‐circuit voltage of 1.184 V. Furthermore, the unencapsulated PDADI‐modified PSCs also exhibit good storage stability, retaining 91% of initial PCE at 65 °C in a N2 glove box for 1300 h. This strategy provides an efficient route to fabricate highly efficient and stable inverted p‐i‐n structured PSCs. 1,3‐diaminopropane dihydroiodide (PDADI) is introduced to modify the perovskite/electron transporting layer (ETL) interface. Based on this strategy, the PDADI‐modified p‐i‐n perovskite solar cells deliver an impressive efficiency of 25.09% (certified 24.58%) at the laboratory scale (0.071 cm2) with an open‐circuit voltage of 1.184 V.