Excellent field emission properties of vertically oriented CuO nanowire films

Long Feng,Rui Chi,Hui Yan,Rukang Zhang,Jiwen Liu,Shuaiyu Yang,Yaya Ma,Heng Li,Zhe Li,Bin Fu

doi:10.1063/1.5022320

Abstract

Oriented CuO nanowire films were synthesized on a large scale using simple method of direct heating copper grids in air. The field emission properties of the sample can be enhanced by improving the aspect ratio of the nanowires just through a facile method of controlling the synthesis conditions. Although the density of the nanowires is large enough, the screen effect is not an important factor in this field emission process because few nanowires sticking out above the rest. Benefiting from the unique geometrical and structural features, the CuO nanowire samples show excellent field emission (FE) properties. The FE measurements of CuO nanowire films illustrate that the sample synthesized at 500 °C for 8 h has a comparatively low turn-on field of 0.68 V/μm, a low threshold field of 1.1 V/μm, and a large field enhancement factor β of 16782 (a record high value for CuO nanostructures, to the best of our knowledge), indicating that the samples are promising candidates for field emission applications.

Highlights

Over the past several decades, extensive efforts have been paid on the field emission (FE) technology due to its numerous applications such as flat-panel display, microwave amplifiers and vacuum microelectronic devices
There are still a lot of research activities focusing on field emission from carbon nanotubes,[3,4] much attention has been paid to other quasi-one-dimensional nanomaterials recently in the hope of avoiding the disadvantages of carbon nanotubes, such as high preparation temperature, high work function, and degradation caused by oxidation or heating effects.[5,6,7]
X-ray diffraction (XRD) measurements were performed on a D/MAX-2500 X-ray diffractometer to study the composition of the products

Summary

Introduction

Over the past several decades, extensive efforts have been paid on the field emission (FE) technology due to its numerous applications such as flat-panel display, microwave amplifiers and vacuum microelectronic devices. The vertically oriented CuO nanowire films synthesized at 500 ◦C for 8 h has the excellent FE properties, with a comparatively low turn-on field of 0.68 V/μm, a low threshold field of 1.1 V/μm, and a large field enhancement factor β of 16782.

Results

Conclusion