Facile synthesis of highly dispersed Fe(II)-doped g-C3N4 and its application in Fenton-like catalysis

Abstract

In this work, highly dispersed Fe(II)-doped g-C3N4 was successfully prepared by simple calcination of a Fe+3/melamine precursor in a semi-closed alumina crucible at 550°C without atmosphere protection. The morphology, structure, and chemical composition of the products were characterized fully. Thermogravimetric analysis/Differential thermic analysis (TGA/DTA), 57Fe Mossbauer, and electron paramagnetic resonance measurements were used to evaluate the changes in the chemical composition of the 10%-Fe/melamine precursor as a function of the calcination temperature, revealing that reduction of Fe+3 to Fe+2 occurs progressively at temperatures between 310°C and 550°C. The prepared Fe-doped g-C3N4 materials exhibit high activity in the Fenton-like degradation of cationic methylene blue within a wide pH range, as well as high reusability and low iron leaching. The catalysts display high activity in the degradation of cationic rhodamine B, anionic indigo carmine (IC), and neutral phenol. Electrospray ionisation mass spectrometry (ESI-MS) measurements confirmed that all selected substrates were successively oxidized into different intermediate compounds before mineralization, exhibiting great potential for application in the degradation of environmental pollutants.