Enhanced photocatalytic activity of ZnO microflower arrays synthesized by one-step etching approach

A new type of ZnO microflower arrays was successfully synthesized via a one-step etching route based on chemical bath disposition (CBD) method without any assistant reagents. The inner and outer wall surfaces of ZnO microflowers are quite smooth with the average thickness of 50 nm. The formation mechanism is proposed that ZnO microflowers were evolved from microrods by preferential etching in reaction solution. ZnO microrod arrays and microcandle arrays were also obtained by varying reaction time. Photoluminescence and photocatalysis properties of ZnO samples were investigated at room temperature. Superior photocatalytic activity of ZnO microflower arrays in the degradation of RhB compared to other samples under identical conditions has been demonstrated, and the origin is mainly ascribed to the increasing surface area and higher oxygen vacancies density of ZnO microflower with partial hollow structure. (c) 2013 Published by Elsevier B.V.