g-C3N4- and polyaniline-co-modified TiO2 nanotube arrays for significantly enhanced photocatalytic degradation of tetrabromobisphenol A under visible light

An ordered g-C3N4- and polyaniline-modified titanium oxide nanotube array (g-C3N4- and PANI-co-modified TiO2 NTAs) was successfully synthesized and used as a photocatalyst. Polyaniline (PANI) was coated onto TiO2 NTAs by electrochemical polycondensation, and g-C3N4 was deposited via the soaking adsorption method. The photocatalysts were examined by several technologies. The experiments demonstrated that the amount of g-C3N4 and PANT, as well as the initial pH value, had significant effects on the photocatalytic efficiency. The resulting photocatalysts exhibited high visible light photocatalytic ability for tetrabromobisphenol A (TBBPA) for two reasons. First, PANI expanded the light absorption into the visible region. Second, rapid and efficient separation of photoinduced charges from the photo-generated potential difference were produced at the contact interface of g-C3N4 and PANI-co-modified TiO2 NTAs. The center dot OH, center dot O-2(-) and h(+) were dominant components for the photocatalytic degradation of TBBPA. In addition, the g-C3N4 and PANI-co-modified TiO2 NTAs have excellent long-term stability. (C) 2020 Elsevier Ltd. All rights reserved.