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

Abstract

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 PANI, 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 photogenerated potential difference were produced at the contact interface of g-C₃N₄ and PANI-co-modified TiO₂ NTAs. The •OH, [Formula: see text] 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.

Keywords: Photocatalysis; Polyaniline; Tetrabromobisphenol A; Titanium oxide nanotube arrays; g-C(3)N(4).