Atomistic Origin of Photoluminescence Quenching in Colloidal MoS2and WS2Nanoplatelets
Abstract
Large chemical tunability and strong light–matter interactions make colloidal transition metal dichalcogenide (TMD) nanostructures particularly suitable for light-emitting applications. However, ultrafast exciton decay and quenched photoluminescence (PL) limit their potential. Combining femtosecond transient absorption spectroscopy with first-principles calculations on MoS2 and WS2 nanoplatelets, we reveal that the observed sub-picosecond exciton decay originates from edge-located optically bright hole traps. These intrinsic trap states stem from the metal d-orbitals and persist even when the sulfur-terminated edges are hydrogen-passivated. Notably, WS2 nanostructures show more localized and optically active edge states than their MoS2 counterparts, and zigzag edges exhibit a higher trap density than armchair edges. The nanoplatelet size dictates the competition between ultrafast edge-trapping and slower core–exciton recombination, and the states responsible for exciton quenching enhance the catalytic activity. Our work represents an important step forward in understanding exciton quenching in TMD nanoplatelets and stimulates additional research to refine physicochemical protocols for enhanced PL.
Details
- Organisation(s)
-
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
- External Organisation(s)
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Friedrich Schiller University Jena
University of Tübingen
University of Cambridge
- Type
- Article
- Journal
- Nano letters
- Volume
- 26
- Pages
- 3064-3072
- No. of pages
- 9
- ISSN
- 1530-6984
- Publication date
- 11.03.2026
- Publication status
- Published
- Peer reviewed
- Yes
- ASJC Scopus subject areas
- Bioengineering, General Chemistry, General Materials Science, Condensed Matter Physics, Mechanical Engineering
- Electronic version(s)
-
https://doi.org/10.1021/acs.nanolett.5c05893 (Access:
Open
)
