Facile synthesis of ZnAl-layered double hydroxide microspheres with core-shell structure and their enhanced adsorption capability

We have developed a simple solution route for the synthesis of hierarchical ZnAl-layered double hydroxide (ZnAl-LDH) microspheres with core-shell structure, which have great practical application as the efficient adsorbent for wastewater purification. The evolution of the morphology with time suggests that the hierarchical ZnAl-LDH microspheres formed by a stepwise growth mechanism. The results demonstrate that the as-prepared ZnAl-LDH microspheres exhibit more excellent adsorption capacity (523 mg/g) towards methyl orange in aqueous solutions as compared with the LDH microspheres previously reported, result of which is attributed to their enhanced surface area and suitable mesopore distribution. This work provides a promising approach for the synthesis of hierarchical porous materials with excellent adsorption capacity, which can be potentially used in wastewater treatment. (C) 2015 Elsevier B.V. All rights reserved.