In:
Nanotechnology, IOP Publishing, Vol. 31, No. 48 ( 2020-11-27), p. 485202-
Abstract:
Full static x-ray computed tomography (CT) technology has enabled higher precision and resolution imaging and has been applied in many applications such as diagnostic medical imaging, industrial inspection and security screening. In this technique, the x-ray source section is mainly composed of a thermionic cathode and electron beam scanning system. However, they have several shortcomings such as limited scanning angle, long response time and large volume. Distributed and programmable cold cathode (i.e. carbon nanotubes, ZnO nanowires (NWs)) field-emission x-ray sources are expected to solve these problems. However, there have been several long-standing challenges to the application of such cold field emitters for x-ray sources, such as the short lifetime and rigorous fabrication process, which have fundamentally prevented their widespread use. Here, we propose and demonstrate a cold field-emission x-ray source based on a graphene oxide (GO)-coated cuprous sulfide nanowire (Cu 2 S NW/GO) cathode. The proposed Cu 2 S NW/GO x-ray source provides stable emission ( 〉 18 h at a direct voltage of 2600 V) and has a low threshold (4.5 MV m −1 for obtaining a current density of 1 μ A cm −2 ), benefiting from the demonstrated key features such as in situ epitaxy growth of Cu 2 S NWs on Cu, nanometer-scale sharp protrusions within GO and charge transfer between the Cu 2 S NWs and GO layer. Our research provides a simple and robust method to obtain a high-performance cold field emitter, leading to great potential for the next generation of x-ray source and CT.
Type of Medium:
Online Resource
ISSN:
0957-4484
,
1361-6528
DOI:
10.1088/1361-6528/abb0b6
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2020
detail.hit.zdb_id:
1362365-5
SSG:
11
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