Efficient photocatalytic degradation of methylene blue dye by SnO2 nanotubes synthesized at different calcination temperatures

Abstract

A template-based liquid phase deposition was applied to fabricate SnO2 nanotube arrays. The prepared SnO2 nanotube photocatalysts were characterized using X-ray diffraction (XRD), field-emission electron microscopy (FE-SEM), transmission electron microscope (TEM), UV–Vis absorb spectrum, and Brunauer-Emmett-Teller (BET) measurements. The results showed that the well-crystalled rutile-SnO2 nanotube arrays with an inner diameter of about 60 nm and a wall thickness of about 20 nm can be fabricated at calcination temperature of 600 °C. In addition, the photocatalytic activity of the SnO2 nanotubes calcined at different temperatures for degradation of methylene blue (MB) dye under UV light illumination was investigated. The results clearly indicated that the samples calcined at 600 °C exhibited the highest photocatalytic activity, which makes them ideal for applications in environmental remediation. It was suggested that the enhanced photocatalytic efficiency of the SnO2 nanotubes may be due to their high specific surface area as-well-as their increased crystallinity with increasing calcination temperature. On the basis of the characterization results, we proposed a possible mechanism for the photocatalytic degradation on SnO2 nanotubes.