Abstract

Attractive attributes of carbon nanotubes (CNTs),, which include high aspect ratio, excellent electrical and thermal conductivity, high melting point, and longer lifetime, have made this one-dimensional material a promising candidate for next-generation field emitters. In the present work, CNTs were grown directly on copper foil, copper foam, nickel foil and nickel foam through chemical vapor deposition. A comparison between CNT-based two-dimensional emitters, i.e. CNTs synthesized on copper and nickel foils, CNT-based three-dimensional (3D) emitters, i.e. CNTs developed on foams of copper and nickel, have been demonstrated. We observed that CNTs on foams exhibited better field emission compared to CNTs synthesized on foils. This is due to the multistage structure of the 3D foams which provides high surface area for CNT growth and hence enhanced field emission response. In the present work, a CNT sample prepared on nickel foam was observed to exhibit better field emission response compared to the other samples synthesized in the present study. This particular sample demonstrateda very low turn-on field of 0.93 V/µm, excellent field enhancement factor of 13,343 and good stability of electron emission.

Graphic Abstract

中文翻译：

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基于碳纳米管的二维和三维场发射体结构

摘要

碳纳米管（CNT）的吸引人的属性包括高长宽比，出色的导电性和导热性，高熔点和更长的使用寿命，使这种一维材料成为下一代场致发射器的有希望的候选者。在目前的工作中，碳纳米管通过化学气相沉积直接在铜箔，泡沫铜，镍箔和泡沫镍上生长。已经证明了基于CNT的二维发射体（即在铜和镍箔上合成的CNT）与基于CNT的三维（3D）发射体（即在铜和镍的泡沫上形成的CNT）之间的比较。我们观察到，与在箔片上合成的CNT相比，泡沫上的CNT表现出更好的场发射。这归因于3D泡沫的多级结构，该结构为CNT生长提供了高表面积，因此增强了场发射响应。在本工作中，与在本研究中合成的其他样品相比，观察到在泡沫镍上制备的CNT样品表现出更好的场发射响应。这个特殊的样品表现出0.93 V / µm的非常低的导通场，出色的13343场增强因子和良好的电子发射稳定性。

图形摘要