Ag nanoparticles loaded TiO2/MWCNT ternary nanocomposite: A visible-light-driven photocatalyst with enhanced photocatalytic performance and stability

A visible light active photocatalyst, Ag/TiO2/MWCNT was synthesized by loading of Ag nanoparticles onto TiO2/MWCNT nanocomposite. The photocatalytic activity of Ag/TiO2/MWCNT ternary nanocomposite was evaluated for the degradation of methylene blue dye under UV and visible light irradiation. Ag/TiO2/MWCNT ternary nanocomposite exhibits (~9 times) higher photocatalytic activity than TiO2/MWCNT and (~2 times) higher than Ag/TiO2 binary nanocomposites under visible light irradiation. The enhancement in the photocatalytic activity is attributed to the synergistic effect between Ag nanoparticles and MWCNT, which enhance the charge separation efficiency by Schottky barrier formation at Ag/TiO2 interface and role of MWCNT as an electron reservoir. Effect of different scavengers on the degradation of methylene blue dye in the presence of catalyst has been investigated to find the role of photogenerated electrons and holes. Simultaneously, the Ag/TiO2/MWCNT shows excellent photocatalytic stability. This work highlights the importance of Ag/TiO2/MWCNT ternary nanocomposite as highly efficient and stable visible-light-driven photocatalyst for the degradation of organic dyes.