Abstract This study presents an eco-friendly mechanochemical synthesis of cesium lead bromide (CsPbBr3), eliminating the need of organic solvents and high temperatures. The synthesized CsPbBr3powder is used to fabricate poly(methyl methacrylate) (PMMA)-CsPbBr3films and CsPbBr3nanocrystals (NCs). The photoluminescence (PL) peaks of the emission light are centered at 541 nm, 538 nm, and 514 nm for the CsPbBr3powder, PMMA-CsPbBr3films, and CsPbBr3NCs, respectively, correlating with crystal sizes of 0.96, 0.56, and 0.12μm, respectively. The PL lifetime analysis reveals decay times ( ) of (4.18, 20.08), (5.7, 46.99), and (5.81, 23.14) in the units (ns, ns) for the CsPbBr3powder, PMMA-CsPbBr3films, and CsPbBr3NCs, respectively. The PL quantum yield of the CsPbBr3NCs in toluene is 61.3%. Thermal activation energies for thermal quenching are 217.48 meV (films) and 178.15 meV (powder), indicating improved thermal stability with the PMMA encapsulation. The analysis of the PL intensity decay from water diffusion in the PMMA-CsPbBr3films yields 1.70 × 10−12m2s−1for the diffusion coefficient of water, comparable to that for water diffusion in pure PMMA. This work demonstrates a scalable, sustainable strategy for CsPbBr3synthesis and stability enhancement for optoelectronic applications.
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Dynamics of poly(methyl acrylate)/poly(methyl methacrylate)-grafted-Fe 3 O 4 nanocomposites
Immiscible blends of poly(methyl acrylate) (PMA) and poly(methyl methacrylate) (PMMA) exhibit component dynamics and dynamics confinement effect at the PMA/PMMA-g-Fe3O4interface, suggesting new routes to control interface dynamics.
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- Award ID(s):
- 2211573
- PAR ID:
- 10586481
- Editor(s):
- Nie, Zhihong
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 20
- Issue:
- 39
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 7970 to 7982
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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