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 μA/cm2 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 sheets of the nanocomposite. The highest current density of ~800 μA/cm2 is drawn at an applied field of 4.1 V/μm 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.

Facile synthesis of differently shaped, ultrathin, and aligned graphene flakes without a catalyst for highly efficient field emission

“…The FE performance of our AGF-SiNW composites is still slightly inferior to the CNT arrays we reported previously [16,25], but it is far better than lots of well-verified good emitters such as single-layer graphenes [10], p-doped graphene nanosheets with layered SnS 2 [40], printed graphene fins [41], and even some one dimensional emitters such as single-crystalline boron nanowire arrays [42], and single-crystalline Sb 2 Se 3 nanowires [43], and it has a good adhesion to the substrates, which is quite different from the CNT-based emitters prepared on Si wafers. The work function (Φ) of the above samples was obtained by using a photoelectron spectrometer, as shown in Table 1.…”

Reduced graphene oxide–titania based platform for label-free biosensor

“…Compared to GO, RGO provides enhanced electrochemical properties, excellent mobility of charge carriers, and can be easily functionalized with biomolecules 14,15,17 due to its large surface area and high density of edge-plane-like defects that may allow fast heterogeneous electron transfer. 18 In addition, ease of processing the material, low cost of synthesis and mechanical exibility of RGO may lead to a wide range of applications, including biosensors, [18][19][20] eld effect transistors, 21 photovoltaics 22 and photodetectors.…”

Microwave‐Assisted Synthesis of Few‐Layered TaTe2 and Its Application as Supercapacitor

“…But the successive layers in TMDC materials are interrelated through weaker van der Waals interlayer forces, which enables these layered materials to be simply exfoliated mechanically. [5,9,12] Further, depending on the mixture of transition metal atom and chalcogen atom, a wide variety of TMDCs are possible such as MoS 2 , [5,9,12,14,17] WS 2 , [13,15,18] MoSe 2 , [16] WSe 2 , [19] MoTe 2 , [20,21] WTe 2 , [22] GaTe, [23] phology, while the XRD data confirms the high crystalline quality and stable phase of the TaTe 2 formed. The supercapacitor cells were fabricated by using TaTe 2 nanosheets as anode material, platinum metal wire as a counterelectrode, and Ag/AgCl as reference electrode.…”