ABSTRACT
The current work reveals notable increase in field emission and photoluminescence characteristics of amorphous carbon nanotubes after forming its composite with In-Situ grown zinc sulfide (ZnS) nanoparticles. An easy chemical technique was employed to synthesize amorphous carbon nanotubes (ACNTs) and then ZnS nanoparticles were grown on them through an In-Situ solvothermal process. The morphology of the ZnS-ACNTs hybrid material was investigated through scanning electron microscope. Photoluminescence and field emission studies of the material were carried out as well in order to realize the applications. Substantial increase in photoluminescence intensity was found for ZnS-ACNTs hybrid material in comparison with pure amorphous carbon nanotubes, the hybrid also turned out as a better field-emitter than pure amorphous carbon nanotubes. Turnon field for ZnS-ACNTs composite decreased to 6 Vµm-1 which was 8 Vµm-1 in case of pure amorphous carbon nanotubes. A simulation analysis following finite element modelling method was carried out which ensured the improvement as field emitter for amorphous carbon nanotubes after ZnS nanoparticles were grown on them. Altogether the hybrid material proved to be a potential candidate for luminescent and cold cathode applications.
ABSTRACT
In the current work we present a simple technique to develop a carbon nanofiber (CNF)/zinc sulfide (ZnS) composite material for excellent FED application. CNFs and ZnS microspheres were synthesized by following a simple thermal chemical vapor deposition and hydrothermal procedure, respectively. A rigorous chemical mixture of CNF and ZnS was prepared to produce the CNF-ZnS composite material. The cathodo-luminescence intensity of the composite improved immensely compared to pure ZnS, also the composite material showed better field emission than pure CNFs. For pure CNF the turn-on field was found to be 2.1 V µm(-1) whereas for the CNF-ZnS composite it reduced to a value of 1.72 V µm(-1). Altogether the composite happened to be an ideal element for both the anode and cathode of a FED system. Furthermore, simulation of our CNF-ZnS composite system using the finite element modeling method also ensured the betterment of field emission from CNF after surface attachment of ZnS nanoclusters.
ABSTRACT
Graphene and carbon nanotubes are very much known as effective field emitter materials. However field emission applications with hybrid carbon nanostructures have mostly remained elusive so far. Here we report, top assembly of very thin layer of reduced graphene oxide (RGO) by Langmuir Blodgett method over a multi-walled carbon nanotubes (MWCNTs) thin film/ITO substrate to investigate the dual field emission property of the hybrid structure. The non-functionalized type of attachment in between the hybrid carbon nanostructures mainly due to van der Waals force of attraction ensured easy fabrication procedure. Evidence of uniform distribution of web like networks of very thin transparent RGO sheets top assembled over densely packed MWCNTs thin film was found from the field emission scanning electron microscopy analysis. The base layer conductivity was enhanced due to the incorporation of MWCNTs bottom layer over ITO and the former also additionally facilitated as emitter site pockets in between RGO planes. Finally, the RGO top assembly resulted in achieving significant improvement in current density and turn-on field in tandem with MWCNTs bottom layer bed making this hybrid system a much feasible candidate for future field emission (FE) based device applications.
