TY - JOUR
T1 - Photo-electrochemical and interfacial-process analysis of WO3 nanostructures supported on TiO2
T2 - An approach to BPA oxidation
AU - Silva-Castro, V.
AU - Durán-Álvarez, J. C.
AU - Mateos-Santiago, J.
AU - Flores-Caballero, A. A.
AU - Lartundo-Rojas, L.
AU - Manzo-Robledo, A.
N1 - Publisher Copyright:
© 2017 Elsevier Ltd
PY - 2017/12
Y1 - 2017/12
N2 - The photo-electrooxidation of bisphenol A (BPA) at the interface of nanostructured materials of TiO2 and WO3-TiO2 was studied under neutral conditions. The tested materials were synthesized via the sol-gel method, and characterized by X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS); as well as electrochemical techniques. X-ray diffraction indicated the formation of pure anatase phase and the presence of monoclinic WO3. XRD-HRTEM revealed WO3 nanoparticles of ca. 5 nm in diameter and anatase nanoparticles of 14.8–24 nm. The XPS analysis confirmed the predominance of WO3 (W6+) and TiO2 (Ti4+) as an heterostructured couple. The semiconductor properties of the synthesized composites were evaluated in 0.1 M KCl using cyclic voltammetry, linear sweep voltammetry, chronoamperometry and electrochemical impedance spectroscopy (EIS). The electrochemical analysis confirmed the formation of the tungsten-oxide bronze sites, and it is proposed that WO3–(OH)ads species are responsible of BPA oxidation. The assays using frequency variation demonstrated that both the flat-band potential and the electrical resistance decrease in the presence of WO3. The evaluation from linear voltammetry during illumination in visible-light region confirmed that the better performance for BPA oxidation was with nanostructured WO3-TiO2 obtaining a faster rate of interfacial electron transfer.
AB - The photo-electrooxidation of bisphenol A (BPA) at the interface of nanostructured materials of TiO2 and WO3-TiO2 was studied under neutral conditions. The tested materials were synthesized via the sol-gel method, and characterized by X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS); as well as electrochemical techniques. X-ray diffraction indicated the formation of pure anatase phase and the presence of monoclinic WO3. XRD-HRTEM revealed WO3 nanoparticles of ca. 5 nm in diameter and anatase nanoparticles of 14.8–24 nm. The XPS analysis confirmed the predominance of WO3 (W6+) and TiO2 (Ti4+) as an heterostructured couple. The semiconductor properties of the synthesized composites were evaluated in 0.1 M KCl using cyclic voltammetry, linear sweep voltammetry, chronoamperometry and electrochemical impedance spectroscopy (EIS). The electrochemical analysis confirmed the formation of the tungsten-oxide bronze sites, and it is proposed that WO3–(OH)ads species are responsible of BPA oxidation. The assays using frequency variation demonstrated that both the flat-band potential and the electrical resistance decrease in the presence of WO3. The evaluation from linear voltammetry during illumination in visible-light region confirmed that the better performance for BPA oxidation was with nanostructured WO3-TiO2 obtaining a faster rate of interfacial electron transfer.
KW - Bisphenol A
KW - Interfacial process
KW - Nanoparticles
KW - Photo-electrocatalysis
KW - Tungsten- oxide
UR - http://www.scopus.com/inward/record.url?scp=85030682887&partnerID=8YFLogxK
U2 - 10.1016/j.mssp.2017.09.014
DO - 10.1016/j.mssp.2017.09.014
M3 - Artículo
SN - 1369-8001
VL - 72
SP - 115
EP - 121
JO - Materials Science in Semiconductor Processing
JF - Materials Science in Semiconductor Processing
ER -