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Effects of Acetone Vapor on the Exciton Band Photoluminescence Emission from Single- and Few-Layer WS₂ on Template-Stripped Gold.

ABSTRACT: Two-dimensional (2D) materials are being used widely for chemical sensing applications due to their large surface-to-volume ratio and photoluminescence (PL) emission and emission exciton band tunability. To better understand how the analyte affects the PL response for a model 2D platform, we used atomic force microscopy (AFM) and co-localized photoluminescence (PL) and Raman mapping to characterize tungsten disulfide (WS₂) flakes on template-stripped gold (TSG) under acetone challenge. We determined the PL-based response from single- and few-layer WS₂ arises from three excitons (neutral, A⁰; biexciton, AA; and the trion, A^-). The A⁰ exciton PL emission is the most strongly quenched by acetone whereas the A^- PL emission exhibits an enhancement. We find the PL behavior is also WS₂ layer number dependent.

SUBMITTER: Matthews S

PROVIDER: S-EPMC6514759 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Effects of Acetone Vapor on the Exciton Band Photoluminescence Emission from Single- and Few-Layer WS<sub>2</sub> on Template-Stripped Gold.

Matthews Samantha S Zhao Chuan C Zeng Hao H Bright Frank V FV

Sensors (Basel, Switzerland) 20190423 8

Two-dimensional (2D) materials are being used widely for chemical sensing applications due to their large surface-to-volume ratio and photoluminescence (PL) emission and emission exciton band tunability. To better understand how the analyte affects the PL response for a model 2D platform, we used atomic force microscopy (AFM) and co-localized photoluminescence (PL) and Raman mapping to characterize tungsten disulfide (WS<sub>2</sub>) flakes on template-stripped gold (TSG) under acetone challenge ...[more]

PMID: 31018501

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