Emitter spacing effects on field emission properties of laser-treated single-walled carbon nanotube buckypapers

Abstract

Carbon nanotube (CNT) emitters on buckypaper were activated by laser treatment and their field emission properties were investigated. The pristine buckypapers and CNT emitters' height, diameter, and spacing were characterized through optical analysis. The emitter spacing directly impacted the emission results when the laser power and treatment times were fixed. The increasing emitter density increased the enhanced field emission current and luminance. However, a continuous and excessive increase of emitter density with spacing reduction generated the screening effect. As a result, the extended screening effect from the smaller spacing eventually crippled the field emission effectiveness. Luminance intensity and uniformity of field emission suggest that the highly effective buckypaper will have a density of 2500 emission spots cm(-2), which presents an effective field enhancement factor of 3721 and a moderated screening effect of 0.005. Proper laser treatment is an effective post-treatment process for optimizing field emission, luminance, and durability performance for buckypaper cold cathodes.

Fabrication and electromechanical performance of carbon nanotube based conductive membrane and its application in real-time multimode strain detection in composites

“…Fibers consisting of CNTs have been used in SHM of damage in structures due to their excellent mechanical behavior, flexibility, and deformation sensitivity [40]- [43]. To have excellent conductivity, CNTs are usually implemented in well-aligned free-standing or a conductive membrane (sheet) of randomly oriented CNTs named as bucky paper [44]- [50]. However, several studies showed that oriented and CNTs grown on a specific substrate required critical control on the fabrication process to ensure better dimension and spacing of CNTs [51]- [53].…”

Transport and field emission properties of buckypapers obtained from aligned carbon nanotubes

“…Nowadays, CNT based field emitters are used in vacuum electronics to produce electron sources [2], flat panels [3], X-ray sources [4,5], and microwave amplifiers [6], exploiting a low-threshold electric field and large emission current density. To increase the extracted current, CNT arrays are usually implemented [7,8] as free-standing well-aligned CNTs [9][10][11] or paper-like sheet of randomly oriented CNTs, named buckypaper [12,13].…”