TiO2 surfaces modified with noble metal nanoparticles have been found to effectively reduce the photogenerated carrier recombination rate and significantly extend the light absorption properties of TiO2, thereby greatly increasing its photocatalytic activity. In this paper, highly ordered, double sided TiO2 nanotube arrays were prepared using an anodic oxidation method in a home-made reactor using glycerol/water (volume ratio 2:1) and NH4F (0.25 mol/L) as the electrolyte, titanium plates (10 cm x 2 cm x 0.5 mm) as the anode and graphite as the cathode at a constant voltage of 25 V. After a 2-h reaction, anatase TiO2 nanotubes were obtained upon calcination at 450 degrees C for 4 h. The Ag nanoparticles on the surfaces of the TiO2 were prepared via ultrasonic atomization-ultraviolet light reduction. First, a silver nitrate solution was sputtered into small droplets under ultrasonication. Then, the Ag+ droplets were reduced to Ag nanoparticles. The surface morphologies, structures and elemental compositions were characterized using SEM, EDS, XRD and XPS. The photocatalytic activities were determined in acetic acid solutions (40-200 mg/L), and a mathematical model for catalytic degradation was established based on a hyperbolic model. The SEM results showed that the diameters of the as-prepared Ag/TiO2 are approximately 100 nm and that the lengths are approximately 1.8 mu m. The XRD crystal structure analysis shows that the anatase phase of the TiO2 does not change during the Ag modification, and there was a peak from Ag (2 2 0). The XPS determined that the Ag atom percentage was 1.11%. The degradation of acetic acid indicated that Ag/TiO2 has a higher photocatalytic activity than the undoped TiO2. (C) 2014 Elsevier B.V. All rights reserved.