Abstract:
A method for manufacturing an electrode for hydrogen production using a tungsten carbide nanoflake may include: forming a tungsten carbide nanoflake on a nanocrystalline diamond film by means of a chemical vapor deposition process in which hydrogen plasma is applied; and increasing activity of the tungsten carbide nanoflake to a hydrogen evolution reaction by removing an oxide layer or a graphene layer from a surface of the tungsten carbide nanoflake. Since an oxide layer and/or a graphene layer of a surface of tungsten carbide is removed by means of cyclic cleaning after tungsten carbide is formed, hydrogen evolution reaction (HER) activity of the tungsten carbide may be increased, thereby enhancing utilization as a catalyst electrode.
Abstract:
2-dimensional nanostructured tungsten carbide which is obtained by control of the alignment of nanostructure during growth of tungsten carbide through control of the degree of supersaturation and a method for fabricating same are disclosed. The method for fabricating 2-dimensional nanostructured tungsten carbide employs a chemical vapor deposition process wherein a hydrogen plasma is applied to prepare 2-dimensional nanostructured tungsten carbide vertically aligned on a nanocrystalline diamond film. The chemical vapor deposition process wherein the hydrogen plasma is applied includes: disposing a substrate with the nanocrystalline diamond film formed thereon on an anode in a chamber, disposing a surface-carburized tungsten cathode above and at a distance from the substrate, and applying the hydrogen plasma into the chamber.
Abstract:
Methods for fabricating uniform nanocrystalline diamond thin films with minimized voids are presented. These uniform nanocrystalline diamond thin films can be formed on any number of treated silicon oxide surfaces such as on hydrogen plasma treated surfaces of silicon oxide-coated substrates or on hydrocarbon plasma pre-treated surfaces of silicon oxide-coated substrates. It is believed that treating these surfaces results in maximizing electrostatic attraction between these treated surfaces with nanodiamond particles during a subsequent ultrasonic seeding of the nanodiamond particles onto these threated surfaces. This can result in the nanodiamond particles being substantially uniformly distributed and bound on the treated silicon oxide surface.
Abstract:
A method for producing a cubic boron nitride (cBN) thin film includes depositing cBN onto nanocrystalline diamond having controlled surface irregularity characteristics to improve the adhesion at the interface of cBN/nanocrystalline diamond, while incorporating hydrogen to a reaction gas upon the synthesis of cBN and controlling the feed time of hydrogen, so that harmful reactions occurring on a surface of nanocrystalline diamond and residual stress applied to cBN may be inhibited. Also, a cBN thin film structure is obtained by the method. The cBN thin film is formed on the nanocrystalline diamond thin film by using a physical vapor deposition process, wherein a reaction gas supplied when the deposition of a thin film occurs is a mixed gas of argon (Ar) with nitrogen (N2), and hydrogen (H2) is added to the reaction gas at a time after the deposition of a thin film occurs.