Design of highly ordered Ag–SrTiO 3 nanotube arrays for photocatalytic degradation of methyl orange

Abstract

Ag–SrTiO 3 nanotube arrays were successfully prepared for the degradation of methyl orange (MO) under ultraviolet irradiation. In order to form highly ordered SrTiO 3 nanotube arrays, the preparation of TiO 2 nanotube arrays by anodic oxidation of titanium foil in different electrolytes was investigated. The selected organic solvents in electrolytes include glycerol, dimethyl sulfoxide and glycol. The results indicate that the morphology of TiO 2 nanotube arrays prepared in glycol containing ammonium fluoride electrolyte is more regular. Then SrTiO 3 nanotube arrays were synthesized by a hydrothermal method using TiO 2 nanotube arrays as the precursor. In order to further improve the photocatalytic activity of SrTiO 3 nanotube arrays, Ag nanoparticles were loaded on SrTiO 3 nanotube arrays by two sets of experiments. The loaded Ag results in an enhancement of photocatalytic activity of SrTiO 3 nanotube arrays. Moreover, the effect of pH on the photocatalytic degradation of MO was also studied.