High-density three-dimension graphene macroscopic objects for high-capacity removal of heavy metal ions.

ABSTRACT: The chemical vapor deposition (CVD) fabrication of high-density three-dimension graphene macroscopic objects (3D-GMOs) with a relatively low porosity has not yet been realized, although they are desirable for applications in which high mechanical and electrical properties are required. Here, we explore a method to rapidly prepare the high-density 3D-GMOs using nickel chloride hexahydrate (NiCl?·6H?O) as a catalyst precursor by CVD process at atmospheric pressure. Further, the free-standing 3D-GMOs are employed as electrolytic electrodes to remove various heavy metal ions. The robust 3D structure, high conductivity (~12?S/cm) and large specific surface area (~560?m²/g) enable ultra-high electrical adsorption capacities (Cd²? ~ 434?mg/g, Pb²?~ 882?mg/g, Ni²? ~ 1,683?mg/g, Cu²? ~ 3,820?mg/g) from aqueous solutions and fast desorption. The current work has significance in the studies of both the fabrication of high-density 3D-GMOs and the removal of heavy metal ions.

SUBMITTER: Li W 

PROVIDER: S-EPMC3699809 | biostudies-other | 2013

REPOSITORIES: biostudies-other