Synthesis of tin oxide (SnO & SnO_2) microanostructures with novel distribution characteristic and superior photocatalytic performance

摘要

SnO microanostructures with novel distribution characteristic of concentric annulus were successfully synthesized by electrochemical anodization of tin foils in sodium hydroxide electrolyte. The SnO structures near the central fracture region were uniform and well-defined octahedron-like. The SnO structures away from the fracture region gathered together and presented petal-like and flower-like patterns. The effects of anodizing parameters and annealing temperatures on the structure features of tin oxide microanostructures were systematically investigated. We found that as-anodized SnO microanostructures can be transformed to tetragonal phase SnO2 microanostructures by a thermal annealing process, which still maintained its original structure features as well as distribution characteristic. The optical property and photocatalytic performance of the annealed samples were also analyzed. The high photocatalytic property of the sample annealed at 400 degrees C was attributed to the strong light absorption and efficient interfacial charge separation. Additionally, a synthesis mechanism was discussed to illustrate the evolution process of anodized SnO microanostructures with the distribution characteristic of concentric annulus. (C) 2016 Elsevier Ltd. All rights reserved.