X-ray Tube Using a Graphene Flower Cloth Field Emission Cathode

Abstract

We have successfully fabricated a filament-less X-ray tube using a graphene flower cloth (GFC) field emission cathode. The GFC has numerous nanoprotrusions formed by self-standing graphene structures. The field emission current and the field enhancement factor were 500 A and 5600, respectively. The stability of voltage defined as a variance coefficient (/mean) of voltage was calculated to be 0.04% while maintaining the X-ray tube current of 300 A. We applied our X-ray tube with the GFC field emitter to the X-ray fluorescence (XRF) analysis of stainless steel.

Self-Assembly of Soot Nanoparticles on the Surface of Resistively Heated Carbon Microtubes in Near-Hexagonal Arrays of Micropyramids

“…The arrays of the carbon micropyramids may be explored as the field emitter arrays. ,, As a first proof of concept, we present here preliminary results to test the capacity of field emission properties of individual pyramids. We used a micronanoprobing station mounted in a scanning electron microscope (see Figure a).…”

“…Carbon is known for its capacity to form numerous architectures on the nanoscale as well as on the microscale. Apart of the most well-known carbon single and multishell tubes, fullerenes, and graphene, there have been discovered many interesting entities such as carbon nanohorns and nanocones, − conical microcrystals, carbon whiskers, , graphite micropyramids, graphene flowers, and vertical graphene. − The electrical, optical, and morphological peculiarities of these architectures give them prospects for advanced applications such as field electron emission sources, , supercapacitors, biosensors, ultrablack materials, and superhydrophobic and bactericidal coatings. The methods of production of these structures include argon plasma etching of graphite substrates, , reactive sputtering using methane gas, thermal chemical vapor deposition on carbon fibers, reduction of graphene oxide nanosheets, combustion flame deposition, microwave plasma chemical vapor deposition followed by bias-assisted reactive ion etching, and a wood charcoal heat treatment above 2000 °C …”

Highly Sensitive and Stable Humidity Sensor Based on the Bi-Layered PVA/Graphene Flower Composite Film

“…Herein, for the first time, we demonstrate a unique sorption layer (multi-layered graphene nanostructures known as graphene flower deposited over PVA film), used to fabricate a fast, highly responsive, and extremely sensitive humidity sensor for future applications in printed electronics. GF material has attractive properties such as a large surface area of 500–2500 m 2 /g, transparent nature, remarkable conductivity, and highly crystalline structure [ 43 , 44 , 45 , 46 , 47 ]. As a result, graphene flower can be considered a viable choice for humidity sensing applications.…”

Field Electron Emission from Crumpled CVD Graphene Patterns Printed via Laser-Induced Forward Transfer

“…All these factors make graphene a promising base material for the creation of field emitters. On the other hand, the excellent mechanical properties and chemical stability of graphene make the use of these emitters particularly relevant for the creation of flexible displays and miniaturized X-ray tubes [ 13 , 14 , 15 , 16 , 17 ].…”