Oxygen-doped Graphitic Carbon Nitride Research Articles

Preparation of oxygen-doped graphitic carbon nitride and its visible-light photocatalytic performance on bisphenol A degradation.

A novel metal-free oxygen-doped graphitic carbon nitride (O-g-C3N4) was synthesized by the pre-treatment of bulk graphitic carbon nitride (g-C3N4) with hydrogen peroxide (H2O2), and combined with high-temperature calcination treatment. The obtained 2-O-g-C3N4 catalyst exhibits high activity in visible light photocatalytic degradation of bisphenol A (BPA) with a mineralization rate as high as 62.3%. According to the characterization results of X-ray diffraction, transmission electron microscopy, UV-visible spectroscopy, Brunauer-Emmett-Teller and photoluminescence spectroscopy analyses, the markedly higher visible-light-driven oxidation activity of 2-O-g-C3N4 is attributed to the larger specific surface area, wider range of light responses and low charge recombination rate. Moreover, the trapping experiment shows that superoxide radicals (•O2 -) are the dominant active species in the BPA decomposition process over 2-O-g-C3N4. This study presents a simple and environment-friendly method to synthesise oxygen-doped graphitic carbon nitride.

Facile surfactant assistant synthesis of porous oxygen-doped graphitic carbon nitride nanosheets with enhanced visible light photocatalytic activity

Porous oxygen-doped graphitic carbon nitride nanosheets (xSO-g-C3N4) were prepared using urea and sodium oleate via thermal copolymerization. The modification of electronic structure, especially the formation of midgap, together with porous nanosheets morphology, promoted light harvesting ability and separation rate of charge carriers, facilitating the visible light photocatalytic activity of xSO-g-C3N4.

One-step fabrication of porous oxygen-doped g-C3N4with feeble nitrogen vacancies for enhanced photocatalytic performance

Porous oxygen-doped graphitic carbon nitride (g-C3N4) with feeble nitrogen vacancies was fabricated through thermal polycondensation of melamine with an appropriate amount of polyvinylpyrrolidone. After optimization, the bandgap of g-C3N4 can be narrowed by 0.2 eV and the specific surface area expanded, which contribute to increasing the utilization of solar energy. Consequently, the optimized g-C3N4 exhibits impressive enhancement in photocatalytic hydrogen evolution performance, by nearly 5 times compared with the pristine one under the irradiation of visible light.

Synthesis of highly fluorescent P,O-g-C3N4nanodots for the label-free detection of Cu2+and acetylcholinesterase activity

Highly fluorescent phosphorus, oxygen-doped graphitic carbon nitride nanodots (P,O-g-C3N4nanodots) were synthesized using chemical oxidation and hydrothermal etching of bulk P-g-C3N4obtainedviapyrolysis of phytic acid and melamine.