TY - JOUR
T1 - Green-Emitting Powders of Zero-Dimensional Cs4PbBr6
T2 - Delineating the Intricacies of the Synthesis and the Origin of Photoluminescence
AU - Ray, Aniruddha
AU - Maggioni, Daniela
AU - Baranov, Dmitry
AU - Dang, Zhiya
AU - Prato, Mirko
AU - Akkerman, Quinten A.
AU - Goldoni, Luca
AU - Caneva, Enrico
AU - Manna, Liberato
AU - Abdelhady, Ahmed L.
N1 - Funding Information:
The research leading to these results has received funding from the European Union 7th Framework Program under grant agreement no. 614897 (ERC Consolidator Grant “TRANS-NANO”). The work of D.B. was supported by the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement no. 794560 (RETAIN). We thank Dr. Federico Locardi and Dr. Guilherme Almeida for helpful discussions and suggestions and Dr. Francesca Benevelli (BrukerBiospin) and Pasquale Illiano (University of Milan) for NMR technical assistance.
Funding Information:
The research leading to these results has received funding from the European Union 7th Framework Program under grant agreement no. 614897 (ERC Consolidator Grant "TRANSNANO"). The work of D.B. was supported by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement no. 794560 (RETAIN). We thank Dr. Federico Locardi and Dr. Guilherme Almeida for helpful discussions and suggestions and Dr. Francesca Benevelli (BrukerBiospin) and Pasquale Illiano (University of Milan) for NMR technical assistance.
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/9/24
Y1 - 2019/9/24
N2 - A detailed investigation into the synthesis of green-emitting powders of Cs4PbBr6 and CsPbBr3 materials by antisolvent precipitation from CsBr-PbBr2 precursor solutions in dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) is reported. Various solvated lead bromide and polybromide species (PbBr2, [PbBr3]-, [PbBr4]2-, and possibly [PbBr5]3- or [PbBr6]4-) are detected in the precursor solutions by optical absorbance and emission spectroscopies. The solvodynamic size of the species in solution is strongly solvent-dependent: ∼1 nm species were detected in DMSO, while significantly larger species were observed in DMF by dynamic light scattering. The solvodynamic size of the lead bromide species plays a critical role in determining the Cs-Pb-Br composition of the precipitated powders: smaller species favor the precipitation of Cs4PbBr6, while larger species template the formation of CsPbBr3 under identical experimental conditions. The powders have been characterized by 133Cs and 207Pb solid-state nuclear magnetic resonance, and 133Cs sensitivity toward the different Cs environments within Cs4PbBr6 is demonstrated. Finally, the possible origins of green emission in Cs4PbBr6 samples are discussed. It is proposed that a two-dimensional Cs2PbBr4 inclusion may be responsible for green emission at ∼520 nm in addition to the widely acknowledged CsPbBr3 impurity, although we found no conclusive experimental evidence supporting such claims.
AB - A detailed investigation into the synthesis of green-emitting powders of Cs4PbBr6 and CsPbBr3 materials by antisolvent precipitation from CsBr-PbBr2 precursor solutions in dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) is reported. Various solvated lead bromide and polybromide species (PbBr2, [PbBr3]-, [PbBr4]2-, and possibly [PbBr5]3- or [PbBr6]4-) are detected in the precursor solutions by optical absorbance and emission spectroscopies. The solvodynamic size of the species in solution is strongly solvent-dependent: ∼1 nm species were detected in DMSO, while significantly larger species were observed in DMF by dynamic light scattering. The solvodynamic size of the lead bromide species plays a critical role in determining the Cs-Pb-Br composition of the precipitated powders: smaller species favor the precipitation of Cs4PbBr6, while larger species template the formation of CsPbBr3 under identical experimental conditions. The powders have been characterized by 133Cs and 207Pb solid-state nuclear magnetic resonance, and 133Cs sensitivity toward the different Cs environments within Cs4PbBr6 is demonstrated. Finally, the possible origins of green emission in Cs4PbBr6 samples are discussed. It is proposed that a two-dimensional Cs2PbBr4 inclusion may be responsible for green emission at ∼520 nm in addition to the widely acknowledged CsPbBr3 impurity, although we found no conclusive experimental evidence supporting such claims.
UR - http://www.scopus.com/inward/record.url?scp=85072881677&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.9b02944
DO - 10.1021/acs.chemmater.9b02944
M3 - Article
AN - SCOPUS:85072881677
SN - 0897-4756
VL - 31
SP - 7761
EP - 7769
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 18
ER -