Abstract
While liquid exfoliation is a powerful technique to produce defect-free nanosheets in large quantities, its usefulness is limited by broad nanosheet thickness distributions and low monolayer contents. Here we demonstrate liquid processing techniques, based on iterative centrifugation cascades, which can be designed to achieve either highly efficient nanosheet size-selection and/or monolayer enrichment. The resultant size-selected dispersions were used to establish quantitative metrics to determine monolayer volume fraction, as well as mean nanosheet size and thickness, from standard spectroscopic measurements. Such metrics allowed us to design and optimize centrifugation cascades to enrich liquid exfoliated WS2 dispersions up to monolayer contents of 75%. Monolayer-rich dispersions show relatively bright photoluminescence with narrow line widths (<35 meV) indicating the high quality of the nanosheets. The enriched dispersions display extinction spectra with distinct features, which also allow the direct estimation of monolayer contents.
Original language | English |
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Pages (from-to) | 1589-1601 |
Number of pages | 13 |
Journal | ACS Nano |
Volume | 10 |
Issue number | 1 |
Early online date | 5 Jan 2016 |
DOIs | |
Publication status | Published - 12 Jan 2016 |
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Dive into the research topics of 'Production of highly monolayer enriched dispersions of liquid-exfoliated nanosheets by liquid cascade centrifugation'. Together they form a unique fingerprint.Profiles
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Elton Santos
- School of Physics and Astronomy - Reader in Theoretical/Computational Condensed Matter Physics
Person: Academic: Research Active