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Graphitic carbon nitride can be made by polymerization of cyanamide, dicyandiamide or melamine. The firstly formed polymeric C 3 N 4 structure, melon, with pendant amino groups, is a highly ordered polymer. Further reaction leads to more condensed and less defective C 3 N 4 species, based on tri-s-triazine (C 6 N 7) units as elementary building ...
References. [3][4][5] Graphite (/ ˈɡræfaɪt /) is a crystalline allotrope (form) of the element carbon. It consists of many stacked layers of graphene typically in the excess of hundred (s) of layers. Graphite occurs naturally and is the most stable form of carbon under standard conditions.
The quality of natural graphite varies as a result of the ore quality and its post-mining processing. The end product is graphite with a content of carbon (high grade graphite 96−98% carbon), sulfur, SiO 2, and ash. The higher the carbon content and the degree of graphitization (high crystalline) the better the lubricity and resistance to ...
A superhard material is a material with a hardness value exceeding 40 gigapascals (GPa) when measured by the Vickers hardness test. [1][2][3][4] They are virtually incompressible solids with high electron density and high bond covalency. As a result of their unique properties, these materials are of great interest in many industrial areas ...
Beta carbon nitride - a solid with a formula β- C3N4, which is predicted to be harder than diamond. Graphitic carbon nitride - g- C3N4, with important catalytic and sensor properties. [2] Dicyanocarbodiimide NC-N=C=N-CN - another C3N4 monomer (was detected in products of photolysis of triazido-s-triazine). [3] C3N5 - a combined triazole and ...
Tungsten carbide (chemical formula: WC) is a chemical compound (specifically, a carbide) containing equal parts of tungsten and carbon atoms. In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes through sintering [7] for use in industrial machinery, cutting tools, chisels, abrasives, armor-piercing shells and jewelry.
The wurtzite form of boron nitride (w-BN; point group = C 6v; space group = P6 3 mc) has the same structure as lonsdaleite, a rare hexagonal polymorph of carbon. As in the cubic form, the boron and nitrogen atoms are grouped into tetrahedra. [6] In the wurtzite form, the boron and nitrogen atoms are grouped into 6-membered rings.
Silicon carbide (SiC), also known as carborundum (/ ˌkɑːrbəˈrʌndəm /), is a hard chemical compound containing silicon and carbon. A wide bandgap semiconductor, it occurs in nature as the extremely rare mineral moissanite, but has been mass-produced as a powder and crystal since 1893 for use as an abrasive.