Controllable construction of graphitic carbon nitride with highly-ordered macropores for boosting photodegradation

Abstract

Graphitic carbon nitride (g-CN) has versatile applications in photocatalysis because of its structural merits, among which the photodegradation of organic pollutants is important. Nonetheless, the limited specific surface area (SSA) and sluggish mass transfer of g-CN restrict its photocatalytic activity. Herein, g-CN with highly ordered macropores (g-CN-HOM-50) was prepared through a harmless, facile and convenient strategy. The research results showed that highly-ordered macropores are greatly advantageous to the properties of the catalyst. The SSA of g-CN-HOM-50 increased to 2.5 times that of bulk g-CN (BCN) measured by nitrogen adsorption–desorption analysis, the mass flow of single g-CN-HOM-50 was enhanced by 7.9% compared to BCN as confirmed by computational fluid dynamics (CFD) simulations and the apparent rate constant (k) of the rhodamine B (RhB) degradation reaction improved to 3.5 times that of BCN. Moreover, it was found that the highly ordered macropores prominently affect the band structure and significantly improve the production of reactive oxygen species. This work provides a prospective catalyst for photocatalytic waste water purification and a strategy for the modification of g-CN.