A quasi-hexagonal prism-shaped carbon nitride for photoreduction of carbon dioxide under visible light

A quasi-hexagonal prism-shaped carbon nitride (H-C3N4) was synthesized from urea-derived C3N4 (U-C3N4) using an alkaline hydrothermal process. U-C3N4 decomposition followed by hydrogen bond rearrangement of hydrolyzed products leads to the formation of a quasi-hexagonal prism-shaped structure. The H-C3N4 catalysts displayed superior activity in the photoreduction of CO2 with H2O compared to U-C3N4. The enhanced photocatalytic activities can be attributed to the promotion of incompletely coordinated nitrogen atom formation in the C3N4 molecules.