F. Santomauro, J. Grilj, L. Mewes, G. Nedelcu, S. Yakunin, T. Rossi, G. Capano, A. Al Haddad, J. Budarz, D. Kinschel, D. Ferreira, G. Rossi, Mario Gutiérrez Tovar, D. Grolimund, V. Samson, M. Nachtegaal, G. Smolentsev, M. Kovalenko, M. Chergui
{"title":"光激发无机钙钛矿中的定域空穴和离域电子:用皮秒x射线吸收光谱观察每个原子行为体","authors":"F. Santomauro, J. Grilj, L. Mewes, G. Nedelcu, S. Yakunin, T. Rossi, G. Capano, A. Al Haddad, J. Budarz, D. Kinschel, D. Ferreira, G. Rossi, Mario Gutiérrez Tovar, D. Grolimund, V. Samson, M. Nachtegaal, G. Smolentsev, M. Kovalenko, M. Chergui","doi":"10.1063/1.4971999","DOIUrl":null,"url":null,"abstract":"We report on an element-selective study of the fate of charge carriers in photoexcited inorganic CsPbBr3 and CsPb(ClBr)3 perovskite nanocrystals in toluene solutions using time-resolved X-ray absorption spectroscopy with 80 ps time resolution. Probing the Br K-edge, the Pb L3-edge, and the Cs L2-edge, we find that holes in the valence band are localized at Br atoms, forming small polarons, while electrons appear as delocalized in the conduction band. No signature of either electronic or structural changes is observed at the Cs L2-edge. The results at the Br and Pb edges suggest the existence of a weakly localized exciton, while the absence of signatures at the Cs edge indicates that the Cs+ cation plays no role in the charge transport, at least beyond 80 ps. This first, time-resolved element-specific study of perovskites helps understand the rather modest charge carrier mobilities in these materials.","PeriodicalId":48683,"journal":{"name":"Structural Dynamics-Us","volume":"4 1","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2016-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.4971999","citationCount":"62","resultStr":"{\"title\":\"Localized holes and delocalized electrons in photoexcited inorganic perovskites: Watching each atomic actor by picosecond X-ray absorption spectroscopy\",\"authors\":\"F. Santomauro, J. Grilj, L. Mewes, G. Nedelcu, S. Yakunin, T. Rossi, G. Capano, A. Al Haddad, J. Budarz, D. Kinschel, D. Ferreira, G. Rossi, Mario Gutiérrez Tovar, D. Grolimund, V. Samson, M. Nachtegaal, G. Smolentsev, M. Kovalenko, M. Chergui\",\"doi\":\"10.1063/1.4971999\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We report on an element-selective study of the fate of charge carriers in photoexcited inorganic CsPbBr3 and CsPb(ClBr)3 perovskite nanocrystals in toluene solutions using time-resolved X-ray absorption spectroscopy with 80 ps time resolution. Probing the Br K-edge, the Pb L3-edge, and the Cs L2-edge, we find that holes in the valence band are localized at Br atoms, forming small polarons, while electrons appear as delocalized in the conduction band. No signature of either electronic or structural changes is observed at the Cs L2-edge. The results at the Br and Pb edges suggest the existence of a weakly localized exciton, while the absence of signatures at the Cs edge indicates that the Cs+ cation plays no role in the charge transport, at least beyond 80 ps. This first, time-resolved element-specific study of perovskites helps understand the rather modest charge carrier mobilities in these materials.\",\"PeriodicalId\":48683,\"journal\":{\"name\":\"Structural Dynamics-Us\",\"volume\":\"4 1\",\"pages\":\"\"},\"PeriodicalIF\":2.3000,\"publicationDate\":\"2016-10-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1063/1.4971999\",\"citationCount\":\"62\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Structural Dynamics-Us\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.1063/1.4971999\",\"RegionNum\":2,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Structural Dynamics-Us","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1063/1.4971999","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Localized holes and delocalized electrons in photoexcited inorganic perovskites: Watching each atomic actor by picosecond X-ray absorption spectroscopy
We report on an element-selective study of the fate of charge carriers in photoexcited inorganic CsPbBr3 and CsPb(ClBr)3 perovskite nanocrystals in toluene solutions using time-resolved X-ray absorption spectroscopy with 80 ps time resolution. Probing the Br K-edge, the Pb L3-edge, and the Cs L2-edge, we find that holes in the valence band are localized at Br atoms, forming small polarons, while electrons appear as delocalized in the conduction band. No signature of either electronic or structural changes is observed at the Cs L2-edge. The results at the Br and Pb edges suggest the existence of a weakly localized exciton, while the absence of signatures at the Cs edge indicates that the Cs+ cation plays no role in the charge transport, at least beyond 80 ps. This first, time-resolved element-specific study of perovskites helps understand the rather modest charge carrier mobilities in these materials.
Structural Dynamics-UsCHEMISTRY, PHYSICALPHYSICS, ATOMIC, MOLECU-PHYSICS, ATOMIC, MOLECULAR & CHEMICAL
CiteScore
5.50
自引率
3.60%
发文量
24
审稿时长
16 weeks
期刊介绍:
Structural Dynamics focuses on the recent developments in experimental and theoretical methods and techniques that allow a visualization of the electronic and geometric structural changes in real time of chemical, biological, and condensed-matter systems. The community of scientists and engineers working on structural dynamics in such diverse systems often use similar instrumentation and methods.
The journal welcomes articles dealing with fundamental problems of electronic and structural dynamics that are tackled by new methods, such as:
Time-resolved X-ray and electron diffraction and scattering,
Coherent diffractive imaging,
Time-resolved X-ray spectroscopies (absorption, emission, resonant inelastic scattering, etc.),
Time-resolved electron energy loss spectroscopy (EELS) and electron microscopy,
Time-resolved photoelectron spectroscopies (UPS, XPS, ARPES, etc.),
Multidimensional spectroscopies in the infrared, the visible and the ultraviolet,
Nonlinear spectroscopies in the VUV, the soft and the hard X-ray domains,
Theory and computational methods and algorithms for the analysis and description of structuraldynamics and their associated experimental signals.
These new methods are enabled by new instrumentation, such as:
X-ray free electron lasers, which provide flux, coherence, and time resolution,
New sources of ultrashort electron pulses,
New sources of ultrashort vacuum ultraviolet (VUV) to hard X-ray pulses, such as high-harmonic generation (HHG) sources or plasma-based sources,
New sources of ultrashort infrared and terahertz (THz) radiation,
New detectors for X-rays and electrons,
New sample handling and delivery schemes,
New computational capabilities.