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Title: Enhanced field emission properties of tilted graphene nanoribbons on aggregated TiO{sub 2} nanotube arrays

Abstract

Highlights: • Graphene nanoribbons (GNBs) slanted on aggregate TiO{sub 2} nanotube (A-TNTs) as field-emitters. • Turn-on electric field and field enhancement factor β are dependent on the substrate morphology. • Various quantities of GNRs are deposited on top of A-TNTs (GNRs/A-TNTs) with different morphologies. • With an increase of GNBs compositions, the specimens' turn-on electric field is reduced to 2.8 V/μm. • The field enhancement factor increased rapidly to about 1964 with the addition of GNRs. - Abstract: Graphene nanoribbons (GNRs) slanted on aggregate TiO{sub 2} nanotube arrays (A-TNTs) with various compositions as field-emitters are reported. The morphology, crystalline structure, and composition of the as-obtained specimens were characterized by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and Raman spectrometry. The dependence of the turn-on electric field and the field enhancement factor β on substrate morphology was studied. An increase of GNRs reduces the specimens’ turn-on electric field to 2.8 V/μm and the field enhancement factor increased rapidly to about 1964 with the addition of GNRs. Results show a strong dependence of the field emission on GNR composition aligned with the gradient on the top of the A-TNT substrate. Enhanced FE properties of the modified TNTs can be mainly attributedmore » to their improved electrical properties and rougher surface morphology.« less

Authors:
 [1];  [2]
  1. Department of Information Technology & Communication, Shih Chien University Kaohsiung Campus, Neimen, Kaohsiung 845, Taiwan (China)
  2. Graduate Institute of Electro-Optical Engineering & Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China)
Publication Date:
OSTI Identifier:
22581577
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 79; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRYSTAL STRUCTURE; ELECTRIC FIELDS; ELECTRICAL PROPERTIES; FIELD EMISSION; GRAPHENE; MORPHOLOGY; NANOTUBES; RAMAN SPECTROSCOPY; SCANNING ELECTRON MICROSCOPY; SUBSTRATES; SURFACE PROPERTIES; TITANIUM OXIDES; X-RAY DIFFRACTION

Citation Formats

Hung, Shang-Chao, E-mail: schung99@gmail.com, and Chen, Yu-Jyun. Enhanced field emission properties of tilted graphene nanoribbons on aggregated TiO{sub 2} nanotube arrays. United States: N. p., 2016. Web. doi:10.1016/J.MATERRESBULL.2016.02.046.
Hung, Shang-Chao, E-mail: schung99@gmail.com, & Chen, Yu-Jyun. Enhanced field emission properties of tilted graphene nanoribbons on aggregated TiO{sub 2} nanotube arrays. United States. doi:10.1016/J.MATERRESBULL.2016.02.046.
Hung, Shang-Chao, E-mail: schung99@gmail.com, and Chen, Yu-Jyun. 2016. "Enhanced field emission properties of tilted graphene nanoribbons on aggregated TiO{sub 2} nanotube arrays". United States. doi:10.1016/J.MATERRESBULL.2016.02.046.
@article{osti_22581577,
title = {Enhanced field emission properties of tilted graphene nanoribbons on aggregated TiO{sub 2} nanotube arrays},
author = {Hung, Shang-Chao, E-mail: schung99@gmail.com and Chen, Yu-Jyun},
abstractNote = {Highlights: • Graphene nanoribbons (GNBs) slanted on aggregate TiO{sub 2} nanotube (A-TNTs) as field-emitters. • Turn-on electric field and field enhancement factor β are dependent on the substrate morphology. • Various quantities of GNRs are deposited on top of A-TNTs (GNRs/A-TNTs) with different morphologies. • With an increase of GNBs compositions, the specimens' turn-on electric field is reduced to 2.8 V/μm. • The field enhancement factor increased rapidly to about 1964 with the addition of GNRs. - Abstract: Graphene nanoribbons (GNRs) slanted on aggregate TiO{sub 2} nanotube arrays (A-TNTs) with various compositions as field-emitters are reported. The morphology, crystalline structure, and composition of the as-obtained specimens were characterized by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and Raman spectrometry. The dependence of the turn-on electric field and the field enhancement factor β on substrate morphology was studied. An increase of GNRs reduces the specimens’ turn-on electric field to 2.8 V/μm and the field enhancement factor increased rapidly to about 1964 with the addition of GNRs. Results show a strong dependence of the field emission on GNR composition aligned with the gradient on the top of the A-TNT substrate. Enhanced FE properties of the modified TNTs can be mainly attributed to their improved electrical properties and rougher surface morphology.},
doi = {10.1016/J.MATERRESBULL.2016.02.046},
journal = {Materials Research Bulletin},
number = ,
volume = 79,
place = {United States},
year = 2016,
month = 7
}
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