FePt nanoparticles as heterogeneous Fenton-like catalysts for hydrogen peroxide decomposition and the decolorization of methylene blue

Abstract

In this report, we show that superparamagnetic FePt nanoparticles are highly efficient heterogeneous Fenton-like oxidation catalysts and compare their performance to Fe3O4 nanoparticles using methylene blue dye as the target organic. X-ray diffraction and transmission electron microscopy were used to characterize the structure of the nanoparticles, a superconducting quantum interference device confirmed the magnetic properties, X-ray photoelectron spectroscopy characterized the chemical state of Fe in the nanoparticles, and ultraviolet–visible spectroscopy was used to monitor the heterogeneous Fenton-like reaction. The pseudo-first-order reaction rate constant for 5 ppm FePt nanoparticles was approximately 100 times faster than for 5 ppm Fe3O4 nanoparticles under otherwise identical conditions. Furthermore, a concentration of 2,500 ppm Fe3O4 was required to achieve the same reaction extent as 5 ppm FePt. Thus, FePt nanoparticles are more efficient heterogeneous Fenton-like catalyst for H2O2 decomposition and methylene blue decolorization than Fe3O4. Further, as both types of nanoparticles are superparamagnetic, they can easily be reclaimed and reused.