An innovative transformation of waste toner powder into magnetic g-C3N4-Fe2O3 photocatalyst: Sustainable e-waste management

In this work, we report an ecofriendly and sustainable approach to recycle the waste toner powder enriched in organic residues and magnetic Fe3O4. The direct calcination of waste toner powder at 600 degrees C ensures the complete decomposition of organic residues and transformation of Fe3O4 into useful magnetic Fe2O3 without any single chemical treatments. We also exploit the e-waste derived Fe2O3 as an iron precursor and thiourea for the fabrication of g-C3N4-Fe2O3 photocatalyst through facile one-step calcination process. The obtained Fe2O3 and g-C3N4-Fe2O3 were characterized by XRD, TGA, SEM-EDS, TEM, BET, XPS, UV-vis. DRS, FT-IR, PL, EIS and VSM. The photocatalytic activity of the g-C3N4-Fe2O3 was evaluated by the degradation of Methyl Orange (MO) and Textile Effluents (TE) under sunlight. The resultant g-C3N4-Fe2O3 exhibited better photocatalytic activity than the Fe2O3 and g-C3N4. Owing to the excellent stability and magnetic separation ability, g-C3N4-Fe2O3 composite displayed superb recyclability without loss of significant photocatalytic activity up to five repeated runs and more significantly, it can be recovered magnetically. This novel e-waste recycling strategy may provide new possibilities for a large-scale and low-cost transformation of waste toner powder into magnetically separable photocatalyst for wastewater treatment.