Acetic acid-assisted supramolecular assembly synthesis of porous g-C3N4 hexagonal prism with excellent photocatalytic activity

Graphic carbon nitride (g-C₃N₄) is a kind of promising organic semiconductor in visible light driven photocatalysis due to its metal free, high physicochemical stability and appealing electronic band structure. In this work, a porous hexagonal-prism g-C₃N₄ (ACNH) photocatalyst was successfully synthesized via an acetic acid-assisted supramolecular assembly approach followed by calcination. The resulting ACNH materials have a corrugated and closely packed porous structure, which is composed of thin layers about 30 nm in thickness. The specific surface area of ACNH is as high as 67.7 m² g⁻¹, which is approximately 8-fold of bulk g-C₃N₄. Moreover, the porous structure induces the red shift of the absorption edge and facilitates the photo-induced charge separation of g-C₃N₄. Compared to bulk g-C₃N₄, the ACNH sample exhibits almost 13-fold improvement for the RhB degradation with the rate constant of 0.053 min⁻¹. This finding suggests that the acid-assisted supramolecular assembly may become a feasible method to synthesize g-C₃N₄-based photocatalysts with higher surface area and photocatalytic activity.