Addressing Global Water Pollution: Removal of Malachite Green Using ZnO-ZnFe₂O₄ Composite Nanofibers
Water pollution is a global concern, especially synthetic dyes that negatively impact both the environment and human health. This study demonstrates that ZnO-ZnFe₂O₄ composite nanofibers, fabricated via electrospinning using polyvinylpyrrolidone (PVP) as a mediator, effectively remove malachite green (MG), a dye with potential carcinogenic properties, from water.
🔬 Study Overview
- Fabrication Method: ZnO and ZnFe₂O₄ were mixed in ratios of 1:1, 2:1, and 1:2 to form one-dimensional nanofibers with diameters of 40–60 nm through electrospinning.
- Structural Characteristics: XRD and HRTEM analyses confirmed the coexistence of ZnO’s hexagonal wurtzite structure and ZnFe₂O₄’s cubic spinel structure.
- Surface Area: BET analysis revealed that Zn–Fe(1-1) exhibited the largest specific surface area of 82 m²/g, providing excellent adsorption performance.
💧 Malachite Green Adsorption Performance
- Maximum Adsorption Capacity: Zn–Fe(1-1) achieved a maximum adsorption capacity of 146.77 mg/g, demonstrating superior performance under pH 7 conditions.
- Adsorption Mechanism: The negatively charged surface of the nanofibers electrostatically attracts MG cations, while hydrogen bonding between surface hydroxyl groups and MG molecules plays a key role.
- Reusability: The adsorbent can be regenerated using 0.1M HCl, maintaining over 80% efficiency even after five cycles of reuse.
📈 Practical Application and Future Outlook
This study demonstrates that ZnO-ZnFe₂O₄ nanofibers are effective water treatment materials with high adsorption capacity and reusability, making them promising for industrial wastewater treatment applications.
References
Raut, S., & Sahoo, S. K. (2024). Removal of malachite green using ZnO-ZnFe₂O₄ nanofibers. Results in Surfaces and Interfaces, 17, 100286. [Online]