Fabrication and characterization of copper (II) oxide/iron (III) oxide thin film heterostructures for trace arsenic (III) removal in water

No hay miniatura disponible
Pastrana, Elizabeth C.
Loarte, Steveen J.
Gonzales-Lorenzo, Carlos D.
Alta, Roxana Y.P.
Alarcón, Hugo A.
Título de la revista
Revista ISSN
Título del volumen
Elsevier B.V.
Proyectos de investigación
Unidades organizativas
Número de la revista
In this study, nano-heterostructures based on copper (II) oxide/iron (III) oxide (CuO/α-Fe2O3) thin films were fabricated by a dip-coating technique using aqueous solutions. The heterostructures were deposited on fluorine-doped tin oxide glass substrates varying the CuO film thickness. From a detailed characterization using Fourier transform-infrared and X-ray diffraction the formation of CuO (tenorite)/α-Fe2O3 (hematite) was demonstrated. Atomic force microscopy provided valuable information on the growth of α-Fe2O3 crystals in the heterostructure with a conical-shaped surface. Meanwhile, the field emission scanning electron microscopy cross-section images confirm the formation of well-defined CuO layers under the α-Fe2O3 layers. The optical band gap energies for the heterostructures obtained were estimated from the diffuse reflectance spectra and ranged from 1.41 to 1.51 eV. Photoluminescence analysis revealed an improved separation and faster transfer of photogenerated electrons and holes for the heterostructures. The removal arsenic from an aqueous solution was achieved through the direct adsorption for As(III) and visible light oxidation to As(V). An enhancement of removal efficiency of As(III) for the heterostructures fabricated compared to pristine oxides was obtained. © 2020
The work described in this paper was financially supported by the National Fund for the Scientific and Technological Development (FONDECYT), Grant No. 237–2015-FONDECYT. The authors thank Dr. Breno Pannia Espósito and the LABQAM of the Chemistry Institute of USP for the analysis of the samples. In addition, authors thank Dr. Pierre Ramos Apestegui for his excellent technical assistance with scanning electron microscopy observation.
Palabras clave
Thin film, Arsenic adsorption, Copper oxide, Heterostructure, Iron oxide