Preparation of Ag nanoparticle surface modified TiO2 nanotube arrays and establishment of a catalytic kinetic model

Abstract

In this paper, the highly ordered TiO2 nanotube arrays were prepared by anodic oxidation method. The electrolyte was composed of ammonium fluoride (0.25 mol/L), glycerol and water (volume ratio 2:1). The anodic oxidation voltage was 25 V, time for two hours. The temperature of calcinations was 450°C, time for four hours. The silver nanoparticles were modified on the surface of TiO2 nanotube arrays by the method of ultrasonic atomization. The experimental results showed that the diameter of TiO2 nanotubes was about 120 nm, the wall thickness was about 12 nm, and the diameter of Ag nanoparticles was about 10 nm, which was more evenly distributed on the pipe diameter. Finally, the catalytic kinetic model of Ag-TiO2 photocatalyst was established based on the Langmuir-Hinshelwood (L-H) model.