Abstract:

The hydrogen bond-riched precursors were prepared by mixing melamine and cyanuric acid in aqueous phase. Subsequently, the porous carbon nitride(g-C₃N₄) materials(MC-s-CN) with three-dimensional lamellar curl stacks were prepared by high temperature polymerization. The effect of hydrogen bonds within the precursor on the catalytic performance during the polymerization process was investigated. The results showed that the introduction of hydrogen bonding greatly reduced the blocky stacking of g-C₃N₄ material and increased its specific surface area to 74.111 9 m²/g, which was 8.7 times that of traditional carbon nitride M-CN. The better photogenerated carrier transport rate and lower complexation rate of MC-s-CN were further proved by fluorescence spectroscopy, photocurrent and electrochemical impedance tests. Finally, the degradation effect of simulated rhodamine dye wastewater was 12.52 times higher than that of traditional method. Then, the nanocelluloses oxidized by 2, 2, 6, 6-tetramethylpiperidine oxide were used as the skeleton materials, and the composite aerogel materials(CN-TCA) with large specific surface area and excellent adsorption performance were successfully prepared by directional freezing relying on the cross-linking of intermolecular hydrogen bonds. The CN-TCA was tested to has good photocatalytic degradation performance, and the degradation rate of rhodamine solution reached 91% under 120 min visible light irradiation. Additionally, the CN-TCA had great recycling performance, and the degradation effect was still 94.08% in the original state after five cycles.

Key words: g-C₃N₄, photocatalysis, nano cellulose, aerogel