Activation of graphitic carbon nitride by surface discharge plasma treatment for enhanced photocatalysis

Plasma treatment is conducted under ambient conditions to enhance the photocatalytic performance of g-C₃N₄ and the influence of the gap between the ceramic plate and substrate on the properties of the g-C₃N₄ is investigated. A distance of 2 mm produces higher photocatalytic activity due to the thin nanostructured architecture and oxygen-containing functional groups on the surface of g-C₃N₄. Although the plasma treatment does not alter the surface morphology of the sample up to a gap of 10 mm, chemical functional groups are introduced onto the surface to improve the photocatalytic activity. Our results demonstrate a simple and feasible strategy to improve the photocatalytic performance of metal-free photocatalysts.