Understanding interfacial reactions that occur between the active layer and charge‐transport layers can extend the stability of perovskite solar cells. In this study, the exposure of methylammonium lead iodide (CH3NH3PbI3) thin films prepared on poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)‐coated glass to 70% relative humidity (R.H.) leads to a perovskite crystal structure change from tetragonal to cubic within 2 days. Interface‐sensitive photoluminescence measurements indicate that the structural change originates at the PEDOT:PSS/perovskite interface. During exposure to 30% R.H., the same structural change occurs over a much longer time scale (>200 days), and a reflection consistent with the presence of (CH3)2NH2PbI3is detected to coexist with the cubic phase by X‐ray diffraction pattern. The authors propose that chemical interactions at the PEDOT:PSS/perovskite interface, facilitated by humidity, promote the formation of dimethylammonium, (CH3)2NH2+. The partial A‐site substitution of CH3NH3+for (CH3)2NH2+to produce a cubic (CH3NH3)1−
Organic–inorganic hybrid perovskites (OIHPs) have been explosively investigated mainly due to their potential applications in optoelectronics. Despite the electronic charge transport, phenomena regarding the spin‐polarized electronic transport in OIHPs‐based spintronic devices and the role of ferromagnet/OIHP spinterfaces remain unclear. In this work, the spin injection, accumulation, transport, and detection at room temperature for a vertical perovskite spin valve (PeSV) consisting of Ni/CH3NH3PbI3−
- NSF-PAR ID:
- 10460779
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 6
- Issue:
- 19
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract x [(CH3)2NH2]x PbI3phase explains the structural change from tetragonal to cubic during short‐term humidity exposure. When (CH3)2NH2+content exceeds its solubility limit in the perovskite during longer humidity exposures, a (CH3)2NH2+‐rich, hexagonal phase of (CH3NH3)1−x [(CH3)2NH2]x PbI3emerges. These interfacial interactions may have consequences for device stability and performance beyond CH3NH3PbI3model systems and merit close attention from the perovskite research community. -
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Abstract There has been a great deal of recent interest in extended compounds containing Ru3+and Ru4+in light of their range of unusual physical properties. Many of these properties are displayed in compounds with the perovskite and related structures. Here we report an array of structurally diverse hybrid ruthenium halide perovskites and related compounds: MA2Ru
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