Highly Active Mesoporous Carbon Nitride for Removal of Aromatic Organic Pollutants under Visible Light Irradiation

In this work, we reported the photocatalytic activities of carbon nitride (CN) materials for removal of various aromatic organic pollutants under visible light irradiation. Both bulk carbon nitride (BCN) and mesoporous carbon nitride (MCN) were prepared similarly through thermal polymerization of urea precursor, except that the mesoporous structure was generated onto the MCN via hard template approach using silica nanoparticles. Successful preparations of both BCN and MCN were suggested from various characterization techniques using XRD, DR UV-Visible spectroscopy, nitrogen adsorption-desorption analyzer, and TEM. The prepared BCN and MCN were tested for removal of aromatic organic pollutants, which were benzene, phenol and salicylic acid under visible light irradiation. Both BCN and MCN did not exhibit any photocatalytic activities in the removal of benzene, but active for removals of phenol and salicylic acid. The structure stability and the presence of electron donating group on the organic pollutants were proposed to affect the photocatalytic removal reactions. Owing to the larger BET specific surface area, MCN showed much higher photocatalytic activity than the BCN for removal of phenol and salicylic acid.