Water-assisted prepared porous carbon nitride incorporated AgBr for highly efficient photocatalytic degradation of orange G under visible light

Carbon nitride is a commonly used photocatalyst for the degradation of organic dyes. However, the high rate of charge carrier recombination limit the photocatalytic activity. Here, a series of porous carbon nitride with AgBr nanoparticles (CN/AgBr) heterojunction are fabricated by thermal condensation of urea with the water and an in situ ion exchange approach. The porous structure of CN is beneficial to improve the photocatalytic performance and enhance the absorption of light energy, which is due to the multiple reflections of light within the macropores layered structure. And the incorporation of AgBr inhibit the charge carriers recombination due to the formation of heterojunction with CN. Furthermore, the photocatalytic activity of all samples are evaluated and display excellent activity in the degradation of orange G under visible light illumination. Among them, the CN/AgBr30 perform the most degradation efficiency, with a removal ratio of up to 92% within 10 min, which is attributed to efficient charge separation and transfer. At last, a photocatalytic mechanism is put forward and explained based on the ESR experiments, free radical and hole scavenging experiments and transient response photocurrent results.