3D hierarchical layered double hydroxide/carbon spheres composite with hollow structure for high adsorption of dye

In this paper, a 3D hierarchical layered double hydroxide (LDH)/carbon sphere (CS) composite was prepared via self-assembly method. After calcination, the hollow structure with high surface area was formed due to removing the carbon core, meanwhile, LDH turned into layered double oxide (LDO) which exhibited superior anion adsorption capacity. The formation of the prepared material was confirmed and characterized, and the adsorption mechanism of the obtained material for different charge anionic dyes was further discussed in detail. Under the optimal conditions, the maximum adsorption capacities of the prepared materials for amaranth and Orange II were 638.634 and 849.674 mg/g, separately, which revealed that the materials can be applied into the effective adsorption of anionic dyes, especially those with less charges.