Chloride-based additive engineering for efficient and stable wide-bandgap perovskite solar cells

Journal article

Metal halide perovskite based tandem solar cells are promising to achieve power conversion efficiency beyond the theoretical limit of their single-junction counterparts. However, overcoming the significant open-circuit voltage deficit present in wide-bandgap perovskite solar cells remains a major hurdle for realizing efficient and stable perovskite tandem cells. Here, a holistic approach to overcoming challenges in 1.8 eV perovskite solar cells is reported by engineering the perovskite crystallization pathway by means of chloride additives. In conjunction with employing a self-assembled monolayer as the hole-transport layer, an open-circuit voltage of 1.25 V and a power conversion efficiency of 17.0% are achieved. The key role of methylammonium chloride addition is elucidated in facilitating the growth of a chloride-rich intermediate phase that directs crystallization of the desired cubic perovskite phase and induces more effective halide homogenization. The as-formed 1.8 eV perovskite demonstrates suppressed halide segregation and improved optoelectronic properties.

Authors: Shen, X; Gallant, BM; Holzhey, P; Smith, JA; Elmestekawy, KA

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: Advanced Materials
• Volume: 35
• Issue: 30
• Article number: e2211742
• Publication date: 2023-06-07
• Acceptance date: 2024-03-30
• DOI: 10.1002/adma.202211742
• EISSN: 1521-4095
• ISSN: 0935-9648
• Pmid: 37191054
• Language: English
• Keywords: crystallization mechanism; suppressed halide segregation; perovskite solar cells; halide homogenization; additive engineering