Superparamagnetic Iron Oxide@Carbon Core–Shell Nanoparticles as Advanced Adsorbent for Efficient Removal of As(V) Ions From Wastewater

In this paper, we have employed the facile one-pot process to synthesize superparamagnetic iron oxide@carbon (Fe
₃
O
₄
@C) core-shell nanoparticles by using ferrocene and acetone as a precursor. The Fe
₃
O
₄
@C nanoparticles were successfully produced by using a solvothermal reaction at 200 °C for 24 h. Effects of synthetic conditions such as amount of ferrocene, solvothermal temperature, and reaction time on the microstructure and formation of Fe
₃
O
₄
@C nanoparticles were optimized. The adsorption activity of arsenic(V) ions on the Fe
₃
O
₄
@C nanoparticles was evaluated and compared with pure Fe
₃
O
₄
nanoparticles. The adsorption kinetics process of Fe
₃
O
₄
@C nanoparticles was fit well with the Langmuir isotherm model. The adsorption efficiency of the Fe
₃
O
₄
@C core-shell nanoparticles showed better performance of 2.3 times than that of pure Fe
₃
O
₄
nanoparticles. The adsorption mechanism studies suggest that the enhancement of removal efficiency of Fe
₃
O
₄
@C core-shell nanoparticles was due to improved electrostatic interactions between functional groups presented in outer carbon shell and arsenic(V) ions and therefore increasing adsorption efficiency. With exhibited advantages of low-cost, high-purity, and large-specific surface, the solvothermal-synthesized Fe
₃
O
₄
@C core-shell nanoparticles can be a promising candidate as magnetically separable adsorbent for advanced wastewater treatment applications.