Dojcinovic, et al. used a combustion process to create CoxMg1-xFe2O4 spinel ferrites using citric acid as fuel. Different values of x (0.0, 0.1, 0.3, 0.5, 0.7, 0.9, and 1) were used, and the amorphous particles were calcined for three hours at 700°C The presence of an excessive amount of cobalt resulted in a decrease in the photocatalytic activity, both under visible light and natural light conditions. Interestingly, Co0.9Mg0.1Fe2O4 had a very high activity level of 74.5% throughout 4 hours. MgFe2O4 had the most significant photocatalytic efficiency when exposed to natural sunlight, achieving an 82% degradation rate after 4 hours. In contrast, Co0.1Mg0.9Fe2O4 demonstrated the greatest photocatalytic activity when subjected to visible light, achieving a degradation rate of 79% after 4 hours. In a study by Mondal et al., a chemical coprecipitation process was used to synthesize Zn0.3Ni0.7Fe2O4 (ZNFO) NPs samples with varying particle sizes. X-ray diffraction analysis confirmed the crystalline phase purity and spinel cubic structure formation in all samples. Testing the photocatalytic activity of each nanocatalyst with MB dye revealed that the smallest ZNFO NPs demonstrated the highest efficiency in degrading the dye under light irradiation. Additionally, ZNFO displayed the strongest ability to eliminate free radicals compared to other samples. These results suggest that tailoring the physical properties of Ni-Zn spinel ferrites, particularly by reducing their size, can enhance their functionality. This makes them promising candidates for applications in photocatalysis and as antioxidants. Shukrullah, Shazia, and other researchers created Ni-ZnFe2O4 NPs by the co-precipitation technique to eliminate chromium metal from industrial wastewater. The synthesized NZF NPs hold great promise for wastewater treatment. Their effectiveness stems from a combination of factors: an extensive surface area, precisely controlled size, and a well-organized internal structure. In the experiment, the industrial wastewater was mixed with the described NPs continuously for 20 mins, and the photocatalytic behavior of NZF NPs was investigated using UV-vis spectrophotometry on the suspension of the NPs. The study found that Zn doping in NZF plays a crucial role in enhancing the efficiency of Cr removal from wastewater, particularly under visible light irradiation. Jesudoss, S. K., et al. successfully created Spinel magnetic ferrite Mn1-xNixFe2O4 NPs using a microwave combustion method. They found that Mn0.5Ni0.5Fe2O4 NPs had the best photocatalytic activity in breaking down synthetic indigo carmine dye. The researchers also observed that the NPs had antibacterial effects comparable to that of the antibiotic streptomycin. These results suggest that these NPs could be a promising low-cost photocatalyst for wastewater treatment and environmental remediation. Deepika, et al. used the citrate precursor approach to create cobalt-zinc ferrite with the chemical formula CoxZn1-xFe2O4. It was shown that a rise in cobalt concentration accelerated the breakdown of MB. Under visible light irradiation, the degradation efficiency increased to a maximum of 77% and a minimum of 65% in 1 hour. As a result, they conclude that cobalt-zinc ferrite is a viable material for water filtration and that its degradation efficiency increases with increased cobalt concentration. Researchers investigated spinel NPs (Mg1-xNixFe2O4) synthesized using a chemical coprecipitation method. The study explored their structural, magnetic, optical, and photocatalytic properties. Notably, the materials exhibited light absorption in the visible region, indicating their potential for photocatalytic applications. Furthermore, increasing the nickel content narrowed the band gap energy, enhancing their photocatalytic activity for degrading MB dye. These findings suggest these NPs hold promise for wastewater treatment. Table . Hazardous contaminant removal from wastewater using different bimetal spinel ferrites prepared by different synthesizing methodologies. A study investigated the use of coprecipitation and sol-gel techniques to synthesize a novel hybrid material, Cu0.5Mg0.5Fe2O4-TiO2. This material was designed to target the breakdown of organic dyes present in wastewater. The experiment achieved a successful synthesis of the composite material, with the TiO2 and Cu0.5Mg0.5Fe2O4-TiO2 components averaging around 40.1 nm and 27.9 nm in size, respectively. Importantly, the Cu0.5Mg0.5Fe2O4-TiO2hybrid exhibited superior photocatalytic activity in degrading RhB dye compared to its counterparts, Cu0.5Mg0.5Fe2O4 and TiO2. This finding suggests promising potential for this material in wastewater treatment applications. A study investigated the photocatalytic activity of cobalt-substituted magnesium-zinc ferrites synthesized using a coprecipitation method. The research aimed to assess their ability to degrade coloured and colourless pollutants, including harmful substances like benzimidazole and MB dye, under sunlight irradiation. The results revealed a significant improvement in photocatalytic activity with increasing cobalt content. Notably, MZF3, with the highest cobalt level, demonstrated the most effective MB degradation. These findings suggest that Mg0.5Zn0.5CoxFe2O4 holds promise as a potential catalyst for wastewater treatment applications. Researchers investigated using Fenton chemistry to treat wastewater containing pollutants that resist biodegradation. Their approach involved developing environmentally friendly recoverable ferrites as catalysts. These catalysts were then used in a solar photo-Fenton process under slightly acidic conditions to break down ciprofloxacin (CPX) and carbamazepine (CBZ). The study successfully degraded both pollutants, identifying the degradation pathways. For CPX, the breakdown targeted specific molecular structures within the molecule. CBZ degradation involved the formation of intermediate compounds, which were further transformed through a series of reactions. A study successfully synthesized high-quality ZNF NPs with a narrow size distribution and small diameter. These NPs exhibited significantly improved magnetic properties, making them suitable for applications in photocatalysis and localized magnetic hyperthermia treatments. This enhancement was attributed to the specific positioning of nickel ions within the NP structure. The researchers further evaluated the photocatalytic activity of each NP by measuring its effectiveness in degrading MB dye under visible light irradiation. The results revealed a clear correlation between the concentration of nickel ions and the degradation efficiency, with higher nickel content leading to faster dye degradation. The study demonstrates that incorporating nickel into these spinel ferrites significantly increases their catalytic activity under visible light. Gul, et al. used a quick and inexpensive chemical process called coprecipitation to create AlxZnFe2-xO4 NPs. The material was found to have significant resistance values after an electrical investigation. The synthetic NPs' optical characteristics demonstrated that they were suitable for photocatalysis and could break down the organic chemicals in the water. Zhang, B. B. et al. used a hydrothermal technique to attach Mn0.5Zn0.5Fe2O4 (MZFO) into AC, producing AC NCs with outstanding magnetic response for wastewater treatment. George, et al. prepared Cu-MgFe2O4 (CMFO) NPs using a simple chemical co-precipitation technique, as these NPs can act as effective photocatalysts to remove dye contaminants from wastewater. The antibacterial activity of CMFO NPs was investigated using the agar well diffusion method. Among the samples tested against the Gram-negative and Grampositive bacteria Escherichia coli and Micrococcus luteus, CMFO-2 and CMFO-3 NPs demonstrated the most excellent antibacterial activity, while CMFO-1 NPs showed minimal activity. To test the effectiveness of spinel CMFO NPs at removing dye, organic MB was used in a photo-Fenton operation. Singh et al. conducted a comprehensive study on the effects of adding Ru to sol-gel-prepared MRuxFe2xO4 (MRFO) (M = Ni, Cu: x = 0.0, 0.02, 0.06, 0.1, and 0.4) spinel nanoferrites. The study assessed the photocatalytic activity of MRFO NPs for the degradation of the antibiotic CPX and the Remazol deep red dye. The results showed that Ru-doped nanoferrites were highly effective in degrading both substances. CuRu0.1Fe1.9O4 degraded the drug in 90 mins, while NiRu0.4Fe1.6O4 degraded the dye in just 5 mins. The high degrading efficiency of Ru-doped nanoferrites demonstrates their potential in photocatalysis applications. Chromium absorption from textile effluent was studied by Jemal Fito et al. using Mn-Ni ferrite NC. The NC showed promising results in eliminating chromium from industrial wastewater, and its adsorption mechanism was found to be chemical sorption and monolayer. Hoa et al. used Hydrothermal synthesis to create CoFe2O4 NPs. They then added Ag NPs to the CoFe2O4 NPs with jasmine extract serving as the reducing agent for Ag + ions to create Ag/CoFe2O4 NPs. The catalytic results demonstrated that Ag/ CoFe2O4 NPs could activate peroxymonosulfate (PMS), producing sulfate radicals that can oxidize several dyes, including MB, MO, and RhB. The Ag NPs in the Ag/CoFe2O4 sample were validated to have functions in dye adsorption, 4-nitrophenol reduction, and enhanced antibacterial behaviour. Ag/CoFe2O4 NPs were found to have growth suppression activity against P. aeruginosa and S. aureus. After three consecutive runs, Ag/CoFe2O4 NPs also showed good reusability. These results suggest that Ag/CoFe2O4 material is a viable multifunctional catalyst for the treatment of wastewater.