Fe-Si-B amorphous magnetic nanoparticles as high-efficiency Fenton-like catalysts for rapid degradation of Rhodamine B

Fe-based amorphous alloys have garnered significant attention as high-efficiency Fenton-like catalysts for wastewater treatment due to their unique disordered atomic structure and abundant active sites. However, challenges remain in achieving both ultra-fast degradation kinetics and facile catalyst recovery. In this study, magnetically recoverable Fe-Si-B amorphous nanoparticle catalysts were successfully prepared by the chemical reduction method, and Rhodamine B degradation experiments were carried out under a Fenton-like system. The structural, morphological, compositional, thermal, and magnetic properties of the Fe-Si-B nanoparticles were characterized before and after the catalytic reaction. The results demonstrated that the nanoparticles retained their amorphous structure after the catalytic reaction and exhibited excellent soft magnetic properties with a saturation magnetization of 94.41 emu/g. Under conditions of 5 mM H 2 O 2 , 70 °C temperature, and pH = 3, the catalyst achieved over 99 % degradation efficiency for 20 mg/L Rhodamine B within 2 min at a dosage of only 10 mg/L. The degradation process followed a pseudo-first-order kinetic model with an activation energy as low as 37.62 kJ/mol. Radical quenching experiments indicated that ·OH played a dominant role in the degradation reaction, and the synergistic effect between the amorphous structure and high-density active sites significantly enhanced the generation efficiency of ·OH, thereby improving catalytic performance.