Facile Assembly of Polyaniline/Graphene Oxide Composite Hydrogels as Adsorbent for Cr(VI) Removal

A facile method for the assembly of polyaniline/graphene oxide (PANi/GO) composite hydrogel has been successfully demonstrated by in-situ polymerization of aniline in the presence of phytic acid with the aid of GO. During the polymerization of aniline, the 2D GO nanosheets can regulate the aggregation state of polymer and prompt the formation of the hydrogel. The chemical structure, morphology and mechanical property are investigated by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and compressive stress-strain measurements, et al. Pani/GO composite hydrogel with high surface area and 3D porous nanostructures exhibits higher adsorption capability for Cr(VI) in compared with PANi hydrogel. Pseudo-second-order and Langmuir isotherm models are effectively employed to describe the adsorption behaviors of PANi/GO composite hydrogel. Furthermore, the regeneration experiments indicate that the as-prepared composite hydrogel can remain 73.5% of the original removal capability after five adsorption-desorption cycles. It is expected that the PANi/GO composite hydrogel can be an effective candidate for the removal of Cr(VI) due to the synergistic effects between PANi and GO within the hydrogel network. (C) 2018 Society of Plastics Engineers