Multi-elemental doped g-C3N4 with enhanced visible light photocatalytic Activity: Insight into naproxen Degradation, Kinetics, effect of Electrolytes, and mechanism

The complexity and heterogeneous existence of water pollutants ensures that development of possible large-scale water remediation technologies encompasses mimicking real water compositions. Naproxen (NPX) photo-catalytic degradation in the presence of brilliant black and different electrolytes was tested, under visible light irradiation, with rare earth metals (Ce, Er, Gd, and Sm) doped graphic carbon nitride (CN) prepared via one pot solid state method. The materials were characterized with FESEM, TEM, XRD, PL, XPS, BET, UV-vis DRS, TGA, FTIR, and electrochemical techniques. Doping increased the Urbach energy compared to pristine graphitic carbon nitride due to observed shift in absorption towards the visible range of the electromagnetic spectrum, and there was proposed interaction of dopants and CN which decreased photoexcited electrons and holes recombi-nation. The highest degradation efficiency of 92.9% was obtained at 1% loading of Ce, Er, Gd, and Sm metals in CN (1RECN) under visible light irradiation which was ascribed to Z-scheme formation, enhanced visible light absorption and superoxide anion radical's involvement as the major species based on radical trapping experi-ments. The 1RECN photocatalyst demonstrated remarkable stability with a 3.4 % efficiency reduction after six photocatalytic degradation cycles. The effective and efficient separation and migration of photoexcited electron-hole pairs resulted in their high photodegradation activity compared to other synthesized composites and pristine CN. The fabricated composites provided an interesting perspective for a highly stable multi-elemental doped CN photocatalysts that could be employed for large scale remediation of different classes of organic pollutants.

Automated summary

This study tested the photocatalytic degradation of Naproxen by rare earth metals doped graphitic carbon nitride materials, and found that 1RECN exhibited the highest degradation efficiency under visible light irradiation. The material showed remarkable stability and potential for large scale remediation of organic pollutants.