Tetrabromobisphenol A photoelectrocatalytic degradation using reduced graphene oxide and cerium dioxide comodified TiO2 nanotube arrays as electrode under visible light

Abstract

Tetrabromobisphenol A, one of the most important brominated retardants, is an typical persistent organic pollutant and it is of great value to develop rapid and effective degradation method. Present study established a photoelectrodegradation method with CeO₂ and reduced graphene oxide co-modified TiO₂ nanotube arrays (RGO-CeO₂-TiO₂ NAs), which were successfully synthesized and characterized with scanning electron microscopy (SEM) and Energy Dispersive X Ray Spectrometry (EDX). The SEM Images revealed that the nanotubes had a diameter of about 100 nm and an obvious layer of CeO₂ and RGO on the surface of TiO₂ nanotube arrays. The EDX data exhibited the presence of Ce element. The results demonstrated that TBBPA was degraded at a high degradation rate constant of 0.0191 min^-1, and photogenerated holes played a major role in the degradation reaction. Significant decrease of degradation efficiency was achieved with the presence of EDTA-2Na(hole scavenger), yet while the existence of t-BuOH(OH scavenger) resulted in less inhibition on the degradation. Besides, RGO-CeO₂-TiO₂ NAs exhibited good stability with rarely decline of degradation efficiency for ten reused runs. All these indicated that RGO-CeO₂-TiO₂ NAs were a good catalyst with extraordinary catalytic activity and stability for PEC degradation, and would have great potential in the control and removal of pollutants.

Keywords: CeO(2) and reduced graphene oxide co-modified TiO(2) nanotube arrays; Photoelectrodegradation; Tetrabromobisphenol A.