Attractive Investigation of Zinc Chromium Nanoferrite by a Simple Auto-Combustion Method

Inorganic Non-Metallic Materials Nanoscience Infectious Diseases Chemistry Materials Science Bioengineering Microbiology Materials Chemistry Biochemistry Life Sciences Medicine
nanoferrite structural properties magnetic properties antimicrobial activity

Synthesis and Study of Antimicrobial and Magnetic Properties of ZnFeCrO4 Nanoferrite

Academic Background

Nanoferrites, due to their unique physical and chemical properties, have broad application prospects in various industrial fields. Spinel ferrites, in particular, are highly regarded for their tunable structures, making them attractive for use in magnetic materials, catalysts, sensors, and biomedical applications. Zinc chromium ferrite (ZnFeCrO4), as a complex oxide combining zinc, iron, and chromium, exhibits excellent electrical conductivity, thermal stability, and magnetic properties, making it a potential candidate for energy storage, catalysis, and electronic devices. However, systematic research on its nanoscale synthesis, structural properties, magnetic characteristics, and antimicrobial activity remains limited. Therefore, this study aims to synthesize ZnFeCrO4 nanomaterials using a simple auto-combustion method and systematically investigate their structural, magnetic, and antimicrobial properties at different annealing temperatures, exploring their potential applications in biomedicine and magnetic materials.

Source of the Paper

This paper was co-authored by H. K. Abdelsalam, Yusuf H. Khalafalla, and Asmaa A. H. El-Bassuony. The authors are affiliated with the Higher Institute of Applied Arts, The Egyptian Chinese University, German International University, and Cairo University in Egypt. The paper was published in Bionanoscience in 2025, with the DOI 10.1007/s12668-025-01888-5.

Research Process

1. Sample Preparation

The study used sulfate salts as raw materials to synthesize ZnFeCrO4 nanoferrite via the auto-combustion method. The specific steps are as follows:
1. Raw Material Preparation: Zinc sulfate (ZnSO4·7H2O), ferric sulfate (Fe2(SO4)3·xH2O), and chromium sulfate (Cr2(SO4)3·xH2O) were weighed according to stoichiometry and dissolved separately in deionized water.
2. Reducing Agent Addition: Urea (CO(NH2)2) was added to the mixed solution as a reducing agent, and the mixture was heated on a hot plate at 250°C until foamy ash appeared.
3. Grinding and Calcination: The resulting ash was ground into fine powder and calcined at 600°C and 800°C for 2 hours to prepare samples at different annealing temperatures.

2. Characterization Analysis

  1. X-ray Diffraction (XRD): XRD analysis was performed using Diano Corporation equipment to confirm the crystal structure of the samples. The results showed that the sample annealed at 800°C exhibited a single-phase spinel cubic structure, while the sample annealed at 600°C contained minor impurity phases (such as hematite and maghemite) due to incomplete combustion.
  2. Atomic Force Microscopy (AFM): The morphology and particle size distribution of the samples were analyzed using the non-contact mode of the Wet-SPM-9600 device. The results indicated that the sample annealed at 800°C had larger and more uniformly distributed particles, while the sample annealed at 600°C showed smaller and less uniform particle sizes due to incomplete crystallization.
  3. Magnetic Measurements: The magnetic hysteresis loops (M-H curves) of the samples were measured using the Lake Shore 7410 vibrating sample magnetometer (VSM). The results revealed that the sample annealed at 800°C had higher saturation magnetization (Ms) and lower coercivity (Hc), indicating significantly improved magnetic properties compared to the sample annealed at 600°C.

3. Antimicrobial Activity Testing

The study tested the antimicrobial activity of ZnFeCrO4 nanoparticles against various Gram-positive bacteria (e.g., Bacillus subtilis, Staphylococcus aureus), Gram-negative bacteria (e.g., Escherichia coli, Neisseria gonorrhoeae), and fungi (e.g., Aspergillus flavus, Candida albicans). The results showed that the sample annealed at 800°C exhibited significantly higher efficacy against Neisseria gonorrhoeae compared to the sample annealed at 600°C, but no significant inhibitory effect was observed against fungi.

Main Results

  1. Structural Analysis: XRD and AFM analyses demonstrated that the sample annealed at 800°C had higher crystallinity and more uniform particle size distribution, while the sample annealed at 600°C contained impurity phases and smaller particle sizes due to incomplete combustion.
  2. Magnetic Properties: Magnetic measurements showed that the Ms value of the sample annealed at 800°C was 2.7 times higher than that of the sample annealed at 600°C, while the Hc value decreased by 1.14 times, indicating its potential for magnetic targeting and separation applications.
  3. Antimicrobial Activity: Antimicrobial tests revealed that the sample annealed at 800°C exhibited significant inhibitory effects against Neisseria gonorrhoeae, but its efficacy against other bacteria and fungi was limited.

Conclusion

This study successfully synthesized ZnFeCrO4 nanoferrite using the auto-combustion method and systematically investigated its structural, magnetic, and antimicrobial properties at different annealing temperatures. The results showed that the sample annealed at 800°C exhibited higher crystallinity, stronger magnetic properties, and significant antimicrobial activity, particularly against Neisseria gonorrhoeae. This research provides important experimental evidence for the application of ZnFeCrO4 nanomaterials in biomedicine and magnetic materials.

Research Highlights

  1. Novel Synthesis Method: The use of a simple auto-combustion method for synthesizing ZnFeCrO4 nanomaterials reduces preparation costs and time.
  2. Comprehensive Performance Study: The systematic investigation of the structural, magnetic, and antimicrobial properties of the samples provides comprehensive data support for future applications.
  3. Potential Application Value: The sample annealed at 800°C demonstrates significant advantages in magnetic targeting and antimicrobial applications, indicating broad application prospects.

Other Valuable Information

The study also highlights that the magnetic properties of ZnFeCrO4 nanomaterials are closely related to the annealing temperature, with higher temperatures enhancing crystallinity and magnetic ordering. Additionally, the potential applications of ZnFeCrO4 in energy storage and catalysis are discussed, providing directions for further research.