Investigating cation distribution and photocatalytic response of non-thermal plasma treated MZnFe2O4(M = Ni, Mg, Mn) nanocomposite ferrites

A sol–gel technique was used to synthesize MZnFe₂O₄ (M = Ni, Mg, Mn) spinel ferrite composites. The post-synthesis sintering of the nanocomposites was done at 700 °C for 5 h, followed by non-thermal microwave plasma treatment for 60 min. X-ray diffraction (XRD) analysis of the nanocomposites was conducted to comprehend the cation distribution of pristine and plasma-modified nanocomposites. XRD intensity of peaks for (220), (311), (400) and (440) planes were used to determine the cations distribution using intensity ratio method. The plasma-modified nanocomposites showed a decrease in the intensity ratio of XRD peaks and an increase in the size of the crystallites. The plasma-modified ZnNiFeO₄ showed a photocatalytic activity of 95% against RhB dye, ZnMgFe₂O₄ showed photocatalytic activity of 87%, and ZnMnFe₂O₄ showed a photocatalytic activity of 90%. The key drivers of high dye degradation efficiency are surface functionalization, removal of oxides and reduced band gap of the plasma-modified nanocomposites.

Graphical abstract