Controllable synthesis of honeycomb-structured ZnO nanomaterials for photocatalytic degradation of methylene blue

Nano-carbon spheres with a controllable particle size were prepared by a hydrothermal method, and ZnO nanomaterials with three-dimensional honeycomb structures were successfully fabricated by a liquid-phase coating method using the carbon spheres as the template. The structural and morphological characterizations show that the honeycomb size and pore structure of the honeycomb-structured ZnO nanomaterials can be achieved by adjusting the hydrothermal temperature for preparing carbon spheres and the molar ratio of carbon sphere to zinc acetate. The synthesized ZnO samples exhibit high specific surface area and more surface-active sites. The degradation rate of methylene blue by the honeycomb-structured ZnO nanomaterials with a honeycomb size of 80 nm and a pore wall thickness of 10 nm reaches 95% within 90 min, which exhibits an enhancement of 108% compared with that observed for conventional micron-sized ZnO. It reveals that the structure of honeycomb-like ZnO nanomaterials can be fabricated controllably, further enhancing their surface adsorption capacity and photocatalytic reactivity. (C) 2019 Elsevier B.V. All rights reserved.