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Graphitic carbon nitride (g-C3N4) is a family of compounds with a general formula near to C3N4 and structures based on heptazine units which, depending on reaction conditions, exhibit different degrees of condensation, properties and reactivities. ==Preparation== Graphitic carbon nitride can be made by polymerization of cyanamide, dicyandiamide or melamine. The firstly formed polymeric C3N4 structure, melon, with pendant amino groups, is a highly ordered polymer. Further reaction leads to more condensed and less defective C3N4 species, based on tri-s-triazine (C6N7) units as elementary building blocks. Graphitic carbon nitride can also be prepared by electrodeposition on Si(100) substrate from a saturated acetone solution of cyanuric trichloride and melamine (ratio =1: 1.5) at room temperature. Well-crystallized graphitic carbon nitride nanocrystallites also can be have prepared via benzene-thermal reaction between C3N3Cl3 and NaNH2 at 180–220 °C for 8–12 h. Recently, a new method of syntheses of graphitic carbon nitrides by heating at 400-600ºC of a mixture of melamine and uric acid in the presence of alumina has been reported. Alumina favored the deposition of the graphitic carbon nitrides layers on the exposed surface. This method can be assimilated to an in situ chemical vapor deposition (CVD). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Graphitic carbon nitride」の詳細全文を読む スポンサード リンク
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