Facile fabrication of 3D graphene hydrogel (rGH) for enhanced removal of heavy metal Cr (VI)

Abstract

The reduced graphene hydrogel (rGH) was prepared by chemical reduction method, and removal performance of heavy metal Cr (VI) in static water was studied. The rGH has a three-dimensional structure and narrow pore size distribution, that the adsorption process of Cr (VI) by rGH is in accordance with Langmuir isotherm model, and the maximum adsorption capacity is 139.6 mg·g-1 .The significant adsorption capacity is mainly attributed to the fact that rGH has nano-sheet structure, and maintains the surface adsorption characteristics of graphene with rapid adsorption. The π-π action will reduce the competitive adsorption of water and increase the adsorption capacity.