One‐step hydrothermal synthesis of ZnO microtubes with an efficient photocatalytic activity

Abstract

In this work, the novel rod-like ZnO microtubes were successfully synthesized via one-step simple, non-toxic, fast and economical hydrothermal route. The as-obtained microtubes were characterized in detail with X-ray diffraction, scanning electron microscope, UV–visible diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, steady-state photoluminescence spectrum and surface photovoltage spectroscopy. The photocatalytic activity of the as-obtained microtubes was evaluated by degradation of methylene blue. The results indicated that the ZnO microtubes, exhibited higher photodegradation efficiency of 95% under UV light irradiation (λ ≤ 420 nm) for 20 min. The photodegradation could be described as the pseudo-first-order kinetics with apparent rate constant of 0.126 min-1, which was based on the unique morphology of ZnO. Moreover, ZnO microtubes maintained a good photostability after three consecutive cycles. Unique microtubes can be applied practically for dye waste-water treatment.