Dual‐Site Synergistic Passivation for Highly Efficient and Stable Perovskite Solar Cells. Issue 46 (6th October 2022)

• Record Type: Journal Article
• Authors: Zhang, Wenyuan; He, Lang; Meng, Yan; Kanda, Hiroyuki; Tang, Dongyan; Ding, Bin; Ding, Yong; Nazeeruddin, Mohammad Khaja; Li, Xin
• Is Part Of: Advanced energy materials. Volume 12:Issue 46(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-10-06
• Subjects: 1H‐benzimidazole -- defects passivation -- density functional theory (DFT) -- Lewis acid–base -- perovskite solar cells; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202202189
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Defect passivation has been recognized as an effective strategy to improve efficiency and stability of perovskite solar cells (PSCs). In this work, in‐depth theoretical calculations and experimental characterizations reveal the dual‐site synergistic passivation of 1H‐benzimidazole (BIZ), and the conjugated structure of the benzene ring tends to increase the interaction between BIZ and perovskite. High‐quality perovskite films are thus achieved, with increased grain size, reduced defect density, and suppressed ion migration. Simultaneously, the reduced work function and optimized band alignment promote carrier transport, reducing nonradiative recombination, and loss of open‐circuit voltages, as well as fill factor. Consequently, the target PSC devices achieve a champion power conversion efficiency (PCE) of 24.59%, and 20.49% for perovskite solar module (a designated area of 27.5 cm 2 ). The unencapsulated PSC maintains 91.49% of original PCE after storing in air with an average relative humidity of 40% for 2400 h. Moreover, the device exhibits remarkable the long‐term operational stability, maintaining 90.47% of initial PCE after continuously operating at the maximum power point for 1000 h. This study not only provides insights into the synergistic passivation of BIZ but also provides a strategy for the application of BIZ derivatives in the photovoltaic field. Abstract : 1H‐benzimidazole as a dual‐site passivator is introduced into perovskite precursors, achieving uniform and compact perovskite films with reducing defects, inhibiting ion migration. Simultaneously, the optimized band alignment promotes the separation of electrons and holes. Consequently, the target perovskite solar cell devices show not only improved efficiency but also remarkable stability. Moreover, density functional theory calculations provide insight into the passivation mechanism.