Green One-Pot Synthesis of Mesoporous g-C₃N₄ for Promoted Organic Dyes Photodegradation in Wastewater Treatment

This work provided a green, one-pot route to synthesize mesoporous g-C₃N₄. A series of characterizations revealed that the mesoporous sample maintained the typical structure of g-C₃N₄. The findings displayed that this mesoporous material had enlarged porosity and optical properties. The largest S_BET of the mesoporous sample (32.65 m²/g) was 4.36 times larger than that of the bulk sample (7.48 m²/g). The photoactivity of the prepared photocatalysts was measured by the photocatalytic removal of rhodamine B (RhB). In agreement with the characterization analysis, the mesoporous g-C₃N₄ (99.60%) exhibited a 3.88 times better photocatalytic efficiency than that of bulk g-C₃N₄ (25.63%) and an 11.19 times faster reaction rate in the same period. In addition, the possible mechanism of this photodecomposition reaction was identified by the electron spin resonance (ESR) and trapping tests. The results demonstrated that •O₂^- and ^•OH made contributions, and ^•O₂^- played a dominant role in this process. This research offers a promising method for the synthesis of mesoporous g-C₃N₄ in an environmentally friendly and cost-effective route with remarkably high photoactivity.