Room-Temperature Solid-State Synthesis of Cs3Cu2I5 Thin Films and Formation Mechanism for Its Unique Local Structure.
J Am Chem Soc
; 145(21): 11650-11658, 2023 May 31.
Article
em En
| MEDLINE
| ID: mdl-37192284
ABSTRACT
Blue-emitting Cs3Cu2I5 has attracted attention owing to its near-unity PL quantum yield and applications in DUV photodetectors and scintillators. Its PL properties originate from the unique local structure around the luminescent center, the [Cu2I5]3- polyhedron iodocuprate anion consisting of the edge-shared CuI3 triangle and the CuI4 tetrahedron dimer, which is isolated by Cs+ ions. We found that solid-state reactions between CsI and CuI occur near room temperature (RT) to form Cs3Cu2I5 and/or CsCu2I3 phases. High-quality thin films of these phases were obtained by the sequential deposition of CuI and CsI by thermal evaporation. We elucidated that the formation of interstitial Cu+ and the antisite of I- at the Cs+ site in the CsI crystal through Cu+ and I- diffusion results in the RT synthesis of Cs3Cu2I5. The unique structure formation of the luminescent center was revealed using a model based on the low packing density of the CsCl-type crystal structure, similar sizes of Cs+ and I- ions, and the high diffusivity of Cu+. The self-aligned patterning of the luminous regions on thin films was demonstrated.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Japão