Sustainable versus conventional approaches: dual-doped α-Fe₂O₃ nanoparticles for enhanced photocatalytic and antioxidant performance

Abstract

Dye pollutions are persistent organic pollutants that are receiving much attention. Magnetic nanoparticles (NPs) are substantial compounds for the removal of organic dyes from wastewater. In this study, Azadirachta indica (A. indica) extract and polyvinylpyrrolidone (PVP) polymer were used as an encapsulating agent for Ni/Cu-doped α-Fe₂O₃ NPs. Those NPs exhibit rhombohedral crystals with the crystallite size of 14–22 nm in a spherical shape, which have a saturation magnetization value approximately between 30 and 36 emu·g⁻¹ under ambient conditions. Bismarck brown Y (BBY) and Rhodamine B (RhB) dyes were used to test the photocatalytic activity, and results showed that Fe₂O₃ had a removal efficiency up to 96%‒98% in 60 min. Fe₂O₃ NPs also demonstrated antioxidant potential against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and results suggest that A. indica-encapsulated Fe₂O₃ NPs are potentially fascinating due to greater accessibility of bioactive constituents with antioxidant activities. This research synthesizes biologically generated doped α-Fe₂O₃ NPs with unique structural and morphological features, offering multifunctional applications like antioxidant and photocatalytic capabilities. These novel properties offer potential uses in a diversity of industries, such as environmental cleanup, energy conversion, and biomedical applications.

Graphical abstract

Keywords

antioxidant / environmental remediation / green synthesis / iron oxide / photocatalysis

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