Enhanced photoelectrocatalytic degradation of an acid dye with boron-doped TiO2 nanotube anodes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Processo FAPESP: 2012/183570

Processo FAPESP: 2011/23128-7

Processo FAPESP: 2008/10449-7

The present work evaluates the performance of boron-doped TiO2 nanotubes (B-TiO2 NTs) prepared by electrochemical anodization in the presence of 70, 140, 280 and 560 ppm of boron when activated by UV/visible irradiation. The presence of boron was characterized by FEG-MEV, XRD, DRS, XPS and photocurrent curves, where the maximum values were obtained for B-TiO2 NTs. Assessment of the electrodes were conducted in the hair dye degradation (Acid Yellow 1 dye) and the degradation rate was 2 times higher at the doped electrode containing 280 ppm of boron, where the maximum electrode activation was obtained under UV/vis irradiation. The best results indicate 100% of discoloration and up to 95% of TOC removal when 100 ppm of Acid Yellow 1 dye was treated at B-TiO2 NTs electrode during 120 min at E-app = +1.2 V in 0.01 mol L-1 of Na2SO4 at pH 2. These findings showed that the photoelectrocatalysis is an efficient method to remove hazardous organic compounds from water and B-doped TiO2 electrodes are an important step in the search for efficient and stable catalysts for photo(electro)catalysis.