Fotoeletrólise do BPA com eletrodo WO3-Cu e detecção eletroquímica dos intermediários fenólicos

Bisphenol A (BPA) is an organic compound widely used in the plastics industries, and has been identified as a serious environmental problem because it is an endocrine disruptor [1]. Thus, different methods of degradation and quantification of BPA are currently being proposed. Photoelectrocatalysis is an efficient method for the mineralization of organic compounds and its performance is directly related to the photocatalyst used. Thus, the aim of this work was the development of photocatalysts of copper-doped tungsten oxide (WO3-Cu) to apply them to the photoelectrochemical degradation of BPA. The degradation monitoring was performed with a carbon-glass electrochemical sensor modified with carbon nanotubes and nickel oxide (NiO/MWCNT/GCE) and measurements of UV-Vis spectroscopy. WO3 films were obtained by the modified sol gel method [2] with addition of CuSO4.5H2O. Doping with Cu increased six times the value of the photocurrent when compared to WO3. The films were characterized by X-ray diffraction, scanning electron microscopy and dispersive energy microanalysis (EDX). Monitoring the degradation of BPA and the formation of intermediates during electrochemical degradation were successfully performed by the NiO/MWCNT/GCE sensors [3], Figure 1a. However, absorbance measurements were compromised by the formation of phenolic intermediates. The results of the total organic carbon content showed 75% degradation of BPA, Figure 1b. The WO3-Cu electrode presented potential application in the photoelectrocatalysis of BPA and it was possible to monitor the degradation and the formation of intermediates using sensors.