Records |
Author |
Imran, M.; Ramade, J.; Di Stasio, F.; De Franco, M.; Buha, J.; Van Aert, S.; Goldoni, L.; Lauciello, S.; Prato, M.; Infante, I.; Bals, S.; Manna, L. |
Title |
Alloy CsCdxPb1–xBr3Perovskite Nanocrystals: The Role of Surface Passivation in Preserving Composition and Blue Emission |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
Volume |
32 |
Issue |
|
Pages |
acs.chemmater.0c03825 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Various strategies have been proposed to engineer the band gap of metal halide perovskite nanocrystals (NCs) while preserving their structure and composition and thus ensuring spectral stability of the emission color. An aspect that has only been marginally investigated is how the type of surface passivation influences the structural/color stability of AMX3 perovskite NCs composed of two different M2+ cations. Here, we report the synthesis of blue-emitting Cs-oleate capped CsCdxPb1–xBr3 NCs, which exhibit a cubic perovskite phase containing Cd-rich domains of Ruddlesden–Popper phases (RP phases). The RP domains spontaneously transform into pure orthorhombic perovskite ones upon NC aging, and the emission color of the NCs shifts from blue to green over days. On the other hand, postsynthesis ligand exchange with various Cs-carboxylate or ammonium bromide salts, right after NC synthesis, provides monocrystalline NCs with cubic phase, highlighting the metastability of RP domains. When NCs are treated with Cs-carboxylates (including Cs-oleate), most of the Cd2+ ions are expelled from NCs upon aging, and the NCs phase evolves from cubic to orthorhombic and their emission color changes from blue to green. Instead, when NCs are coated with ammonium bromides, the loss of Cd2+ ions is suppressed and the NCs tend to retain their blue emission (both in colloidal dispersions and in electroluminescent devices), as well as their cubic phase, over time. The improved compositional and structural stability in the latter cases is ascribed to the saturation of surface vacancies, which may act as channels for the expulsion of Cd2+ ions from NCs. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000603288800034 |
Publication Date |
2020-12-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.6 |
Times cited |
44 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
OpenAccess |
Notes |
European Commission; Fonds Wetenschappelijk Onderzoek, G.0267.18N ; H2020 European Research Council, 770887 815128 851794 ; We acknowledge funding from the FLAG-ERA JTC2019 project PeroGas. S.B., and S.V.A. acknowledges funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ERC Consolidator Grants #815128REALNANO and #770887PICOMETRICS) and from the Research Foundation Flanders (FWO, Belgium) through project funding G.0267.18N. F.D.S. acknowledges the funding from ERC starting grant NANOLED (851794). The computational work was carried out on the Dutch National e-infrastructure with the support of the SURF Cooperative; sygma |
Approved |
Most recent IF: 8.6; 2020 IF: 9.466 |
Call Number |
EMAT @ emat @c:irua:174004 |
Serial |
6659 |
Permanent link to this record |
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Author |
Imran, M.; Peng, L.; Pianetti, A.; Pinchetti, V.; Ramade, J.; Zito, J.; Di Stasio, F.; Buha, J.; Toso, S.; Song, J.; Infante, I.; Bals, S.; Brovelli, S.; Manna, L. |
Title |
Halide perovskite-lead chalcohalide nanocrystal heterostructures |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of The American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
143 |
Issue |
3 |
Pages |
1435-1446 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report the synthesis of colloidal CsPbX3-Pb4S3Br2 (X = Cl, Br, I) nanocrystal heterostructures, providing an example of a sharp and atomically resolved epitaxial interface between a metal halide perovskite and a non-perovskite lattice. The CsPbBr3-Pb4S3Br2 nanocrystals are prepared by a two-step direct synthesis using preformed subnanometer CsPbBr3 clusters. Density functional theory calculations indicate the creation of a quasi-type II alignment at the heterointerface as well as the formation of localized trap states, promoting ultrafast separation of photogenerated excitons and carrier trapping, as confirmed by spectroscopic experiments. Postsynthesis reaction with either Cl- or I- ions delivers the corresponding CsPbCI3-Pb4S3Br2 and CsPbI3-Pb4S3Br2 heterostructures, thus enabling anion exchange only in the perovskite domain. An increased structural rigidity is conferred to the perovskite lattice when it is interfaced with the chalcohalide lattice. This is attested by the improved stability of the metastable gamma phase (or “black” phase) of CsPbI3 in the CsPbI3-Pb4S3Br2 heterostructure. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000614064400024 |
Publication Date |
2021-01-15 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
54 |
Open Access ![sorted by Open Access field, descending order (down)](img/sort_desc.gif) |
OpenAccess |
Notes |
This work was performed on the Dutch national e-infrastructure with the support of SURF Cooperative. L.P. and J.S. are thankful for the support by the National Key R&D Program of China (2018YFC0910600) and the National Natural Science Foundation of China (61775145). F.D.S. and S.B. acknowledge support by the European Research Council via the ERC-StG “NANOLED” (851794) and the ERC-Cog “REALNANO” (815128). The authors acknowledge financial support from the European Commission under the Horizon 2020 Programme through Grant Agreement No. 731019 (EUSMI). S.B., A.P., and V.P. gratefully acknowledge the financial support from the Italian Ministry of University and Research (MIUR) through grant “Dipartimenti di Eccellenza2017 Materials For Energy”.; sygma |
Approved |
Most recent IF: 13.858 |
Call Number |
UA @ admin @ c:irua:176584 |
Serial |
6726 |
Permanent link to this record |