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Abstract Lead halide perovskites (LHPs), have attracted considerable attention across various applications owing to their exceptional optoelectronic properties. However, the main challenge hindering the broad adoption of lead halide perovskites lies in their stability and toxicity. In this review, we summarize the outstanding properties of platinum (Pt) halide perovskites, with a particular focus on the stability and applications of Cs2PtI6and its derivatives. Cs2PtI6has shown promising efficiency for photovoltaic devices, as well as photoelectrochemical water splitting with stable behavior in acid or basic conditions. Cs2PtI6also shows promise in gas sensing and thermoelectric devices. The emergence of 2D Pt (II) halide perovskites opens up new avenues for environmentally friendly materials for photonic and optoelectronic devices like room temperature phosphoresce and triplet‐triplet annihilation (TTA) based up‐conversion. image
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This content will become publicly available on February 1, 2026
In situ formation of pseudohalide anions induced by humid air and light passivates formamidinium‐based halide perovskites
Abstract Metal halide perovskites based on formamidinium (FA), or FA‐rich compositions have shown great promise for high‐performance photovoltaics. A deeper understanding of the impact of ambient conditions (e.g., moisture, oxygen, and illumination) on the possible reactions of FA‐based perovskite films and their processing sensitivities has become critical for further advances toward commercialization. Herein, we investigate reactions that take place on the surface of the FA0.7Cs0.3, mixed Br/I wide bandgap perovskite thin films in the presence of humid air and ambient illumination. The treatment forms a surface layer containing O, OH, and N‐based anions. We propose the latter originates from formamidine trapped at the perovskite/oxide interface reacting further to cyanide and/or formamidinate—an understudied class of pseudohalides that bind to Pb. Optimized treatment conditions improve photoluminescence quantum yield owing to both reduced surface recombination velocity and increased bulk carrier lifetime. The corresponding perovskite solar cells also exhibit improved performance. Identifying these reactions opens possibilities for better utilizing cyanide and amidinate ligands, species that may be expected during vapor processing of FA‐based perovskites. Our work also provides new insights into the self‐healing or self‐passivating of MA‐free perovskite compositions where FA and iodide damage could be partially offset by advantageous reaction byproducts. image
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- Award ID(s):
- 2043205
- PAR ID:
- 10575765
- Publisher / Repository:
- John Wiley & Sons, Inc
- Date Published:
- Journal Name:
- InfoMat
- Volume:
- 7
- Issue:
- 2
- ISSN:
- 2567-3165
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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