Ligand Homogenized Br–I Wide-Bandgap Perovskites for Efficient NiO x ‑Based Inverted Semitransparent and Tandem Solar Cells

• Published in: ACS nano Vol. 18; no. 24; pp. 15991 - 16001
• Main Authors: Zhang, Xing, Ma, Qiaoyan, Wang, Yousheng, Zheng, Jianzha, Liu, Quanxi, Liu, Liming, Yang, Peng, He, Wujie, Cao, Ye, Duan, Weiyuan, Ding, Kaining, Mai, Yaohua
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 18.06.2024
• Subjects: Homogenized Br−I halides; Semitransparent and tandem solar cells; Phase heterogeneity; Wide-bandgap perovskites; Ligand anchoring heterointerface
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.4c04341

Phase heterogeneity of bromine–iodine (Br–I) mixed wide-bandgap (WBG) perovskites has detrimental effects on solar cell performance and stability. Here, we report a heterointerface anchoring strategy to homogenize the Br–I distribution and mitigate the segregation of Br-rich WBG-perovskite phases. We find that methoxy-substituted phenyl ethylammonium (x-MeOPEA+) ligands not only contribute to the crystal growth with vertical orientation but also promote halide homogenization and defect passivation near the buried perovskite/hole transport layer (HTL) interface as well as reduce trap-mediated recombination. Based on improvements in WBG-perovskite homogeneity and heterointerface contacts, NiO x -based opaque WBG-perovskite solar cells (WBG-PSCs) achieved impressive open-circuit voltage (V oc) and fill factor (FF) values of 1.22 V and 83%, respectively. Moreover, semitransparent WBG-PSCs exhibit a PCE of 18.5% (15.4% for the IZO front side) and a high FF of 80.7% (79.4% for the IZO front side) for a designated illumination area (da) of 0.12 cm2. Such a strategy further enables 24.3%-efficient two-terminal perovskite/silicon (double-polished) tandem solar cells (da of 1.159 cm2) with a high V oc of over 1.90 V. The tandem devices also show high operational stability over 1000 h during T90 lifetime measurements.