Synthesis and enhanced photocatalytic activity of 3D flowerlike ZnO microstructures on activated carbon fiber

• 3D flowerlike ZnO microstructures with wurtzite phase attached onto ACF were fabricated by a hydrothermal method.
• Flowerlike structures were built up by multilayered petals and the formation mechanism was proposed.
• The ZnO/ACF composite showed a higher photocatalytic activity than pure ZnO in the decomposition of MO.

A hydrothermal method was utilized to attach 3D flowerlike ZnO microstructures to the surface of activated carbon fiber (ACF). The phase structure, morphology and optical property of the obtained sample were characterized. SEM demonstrated that the flowerlike structures consisted of multilayered petals, which were wholly comprised of ZnO rods. XRD analysis confirmed patterns for the wurtzite hexagonal phase of ZnO and ACF from the sample. The formation mechanism of the flowerlike ZnO grown on ACF was also discussed. The ZnO/ACF composite showed a superior photocatalytic activity in the degradation of methyl orange as compared with pure ZnO. The enhancement was attributed to a red shift, stronger UV light absorption ability and higher absorption behavior in ZnO/ACF, and the capture and transportation of photogenerated electrons by ACF.