Incorporation of iodine on Ag3PO4 under Nigella Sativa seed extract for enhanced photocatalytic activity

Abstract

The iodine dopant in photocatalysts has new challenges in improving photocatalytic activity. Here, iodine incorporation in Ag₃PO₄ under potassium iodide (KI) and Nigella sativa seed extract has been successfully prepared using the coprecipitation method. The preparation utilized the starting material of Na₂HPO₄.12H₂O, AgNO₃, Nigella sativa seed extract, and KI with variation concentration as sources of iodine dopant. The results revealed that KI addition causes significant changes in the UV-DRS absorption, PL spectra, FTIR, and Raman spectra. The lower concentration of KI treatment resulted in a more effective iodine dopant in the Ag₃PO₄ surface. This treatment lowers the d-space of the Ag₃PO₄ crystal, increases the bandgap energy, and decreases the P/Ag atomic ratio, resulting in I-doped Ag₃PO₄ with phosphate deficiency. The photocatalytic activity showed a significant effect on the degradation of Rhodamine B (RhB), Methylene Blue (MB), and Methyl Orange (MO). This excellent photocatalytic activity is mainly due to a higher active species of holes and superoxide anion radicals.