TiO2/Ag2O-Exfoliated Graphite as Visible ‎Light-Responsive Nanostructure for ‎Improved Photoelectrochemical ‎Degradation of BPA

Document Type : Research Paper


1 ‎Department of Applied Chemistry, University of Johannesburg, ‎ Doornfontein, 2028, Johannesburg, South Africa‎

2 ‎DST-CSIR National Center for Nanostructured Materials, Council for Scientific and ‎Industrial Research, Pretoria 0001, South Africa

3 Tshwane University of Technology, Department of Chemical, Metallurgical and Materials ‎Engineering, Pretoria, South Africa


   In this paper, exfoliated graphite (EG), titanium dioxide (TiO2), silver oxide (Ag2O) and TiO2-Ag2O/ EG have synthesized, fabricated and characterized. An electrolyte used in this work was Bisphenol A (BPA). Degradation was carried out under electrochemical oxidation, photolysis and photoelectrochemical. Characterization techniques utilized were: ultraviolet–visible (UV) diffuse reflectance analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), Raman, thermal gravimetric analyzer (TGA), and X-ray diffractometry (XRD). SEM morphologies, EDX and the XRD patterns showed a good mix and disperse among nanocomposites in terms of the formation of TiO2-Ag2O/EG. Degradation analysis revealed TiO2-Ag2O/ EG as the best nanocomposite for degradation of azo dyes from the wastewater. On a relative view of engaged techniques, photoelectrochemical revealed to be worthwhile.


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