Clay-derived Synthesis of Supported α-Fe2O3 Nanoparticles: Shape, Adsorption, and Photo-catalysis

Abstract

Background: This paper reports a versatile bentonite clay-mediated growth method for selectively synthesizing zero-dimensional α-Fe2O3 nanoparticles and one-dimensional α-Fe2O3 nanorods. Method: In such a growth process without any other surfactant or additive, the bentonite clay is not only used as the supporter, but also as a shape mediator for α-Fe2O3 nanocrystals. The products were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Results: The as-prepared products were used to investigate their promising adsorptive and photocatalytic applications in water treatment. According to the Langmuir equation, the maximum adsorption capacity of the α-Fe2O3/bentonite composite for Congo red (CR) is calculated to be 96.9 mg·g-1. Furthermore, the α-Fe2O3/bentonite nanocomposites also show an excellent photocatalytic property in the degradation of methyl orange (MO). Conclusion: This facile and novel synthesis method has the potential to be applied to prepare the low-cost α-Fe2O3/bentonite nanocomposite for the removal of CR and MO.