Carbon nitride exfoliation for photocatalysis and photocatalytic ozonation over emerging contaminants abatement

The production of graphitic carbon nitride was studied with the addition of a following exfoliation step using ultrasounds, at different times. The treatment produced catalysts with much higher surface areas, from 2.18 m2 g  1 with no treatment to 28.34 m2 g  1 after 36 h of exfoliation. During exfoliation, melem was also produced, and may further enhance the photoluminescence and photocatalytic properties. The photocatalytic reaction also indicated the improved performance of exfoliated g-C3N4 towards the degradation of a mixture of parabens, enhancing their removal from 20% to up to 65% in 2 h under UVA radiation. The combination of ozone and g-C3N4 photocatalysis was able to completely remove the parabens in under 8 min and with a 20% lower con-sumption of ozone compared to photolytic ozonation. The main reactive species were identified, and the by-products formed during parabens degradation were detected. The efficiency of the combined system was also attested by using a mixture of parabens and other common drugs, maintaining its better performance.

Automated summary

In this study, graphitic carbon nitride was synthesized with the addition of an exfoliation step using ultrasounds. The exfoliation process significantly increased the catalyst's surface area, from 2.18 m2 g  1 without treatment to 28.34 m2 g  1 after 36 hours of exfoliation. The formation of melem during exfoliation may further enhance the photoluminescence and photocatalytic properties. The combination of ozone and g-C3N4 photocatalysis showed better performance in the degradation of parabens compared to photolytic ozonation.