Synthesis of beta carbon nitride nanosized crystal through mechanochemical reaction

Nanosized beta carbon nitride (β-C₃N₄), of grain size several tens of nanometres, has been synthesized by mechanochemical reaction processing. The low-cost synthetic method developed facilitates the novel and effective synthesis of nanosized crystalline β-C₃N₄ (a = 6.36 Å, c = 4.648 Å) powders. The graphite powders were first milled to a nanoscale state, then the nanosized graphite powders were milled in an atmosphere of NH₃ gas. It was found that nanosized β-C₃N₄ was formed after high-energy ball milling under an NH₃ atmosphere. After thermal annealing, the shape of the β-C₃N₄ changes from flake-like to sphere-like. The nanosized β-C₃N₄ formed was characterized by x-ray diffraction, Fourier transformation infrared spectroscopy, and transmission electron microscopy. A solid–gas reaction mechanism was proposed for the formation of nanosized β-C₃N₄ at room temperature induced by mechanochemical activation.