[156] Cd0.5Cu0.5xAgxFe2O4 ferrites were studied by Ahmed H., et al. and made using a straightforward coprecipitation process. The standard organic impurity indigo carmine dye (IC), a byproduct of dyeing indigo, was oxidatively broken down using the samples as catalysts. In the pH range of 2-11, Cd0.5Cu0.5-xAgxFe2O4 showed good catalytic activity, making them promising, stable, and effective materials for Fenton-based alkaline wastewater treatment. Researchers investigated a rapid and cost-effective method (sol-gel and selfcombustion) to synthesize scandium (Sc)-doped nickel-cobalt ferrite NPs (Ni0.5Co0.5ScxFe2xO4). The resulting materials exhibited nanoscale crystallinity (ranging from 35 to 42 nm). The study explored the impact of Sc substitution on the catalytic activity of these ferrites. This was evaluated by analyzing the flameless combustion of acetone, propane, and benzene in the presence of the different samples. The findings revealed a clear benefit of replacing some iron (Fe 3+ ) ions with Sc 3+ ions within the ferrite structure. Notably, the Sc-doped catalysts achieved conversion rates exceeding 90% for acetone or propane at a temperature of 400°C. This enhanced catalytic activity compared to pure Ni-Co ferrites is likely due to a combination of factors, including smaller crystallite size, larger specific surface area, and the incorporation of Sc cations within the material's structure. Researchers investigated magnesium-zinc nanoferrites doped with cobalt for wastewater treatment. A simple combustion method produced Mg0.5Zn0.4Co0.1Fe2O4, Mg0.4Zn0.5Co0.1Fe2O4, and Mg0.5Zn0.5Co0.1Fe1.9O4. The synthesized catalysts underwent structural, optical, and magnetic characterization. Notably, the Z5C1 catalyst achieved impressive photocatalytic activity under UV-visible light, degrading 97.76% of CV dye in 90 minutes. This efficiency is attributed to the Z5C1's low charge carrier recombination and suitable band gap. Scavenger studies suggest holes play a key role in breaking down CV dye. The Z5C1 catalyst's reusability and magnetic separation potential highlight its promise for degrading organic pollutants. Table . Tri-metal spinel ferrite materials are used to remove harmful substances from wastewater.