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Superior field emission properties of layered WS2-RGO nanocomposites.

ABSTRACT: We report here the field emission studies of a layered WS2-RGO composite at the base pressure of ~1 × 10(-8) mbar. The turn on field required to draw a field emission current density of 1 ?A/cm(2) is found to be 3.5, 2.3 and 2 V/?m for WS2, RGO and the WS2-RGO composite respectively. The enhanced field emission behavior observed for the WS2-RGO nanocomposite is attributed to a high field enhancement factor of 2978, which is associated with the surface protrusions of the single-to-few layer thick sheets of the nanocomposite. The highest current density of ~800 ?A/cm(2) is drawn at an applied field of 4.1 V/?m from a few layers of the WS2-RGO nanocomposite. Furthermore, first-principles density functional calculations suggest that the enhanced field emission may also be due to an overalp of the electronic structures of WS2 and RGO, where graphene-like states are dumped in the region of the WS2 fundamental gap.

SUBMITTER: Rout CS

PROVIDER: S-EPMC3836036 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Superior field emission properties of layered WS2-RGO nanocomposites.

Rout Chandra Sekhar CS Joshi Padmashree D PD Kashid Ranjit V RV Joag Dilip S DS More Mahendra A MA Simbeck Adam J AJ Washington Morris M Nayak Saroj K SK Late Dattatray J DJ

Scientific reports 20131121

We report here the field emission studies of a layered WS2-RGO composite at the base pressure of ~1 × 10(-8) mbar. The turn on field required to draw a field emission current density of 1 μA/cm(2) is found to be 3.5, 2.3 and 2 V/μm for WS2, RGO and the WS2-RGO composite respectively. The enhanced field emission behavior observed for the WS2-RGO nanocomposite is attributed to a high field enhancement factor of 2978, which is associated with the surface protrusions of the single-to-few layer thick ...[more]

PMID: 24257504

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Superior field emission properties of layered WS2-RGO nanocomposites.

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Superior field emission properties of layered WS2-RGO nanocomposites.

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