3D hierarchical porous graphene aerogels for highly improved adsorption and recycled capacity

•3D HGAs were prepared by a “fishing” process.•Their porous morphologies were varied by changing of PS particles.•HGAs are used as adsorbents for removal of oils and organic solvents.•They exhibit highly improved adsorption and recycled capacity. This article demonstrates the fabrication of 3D hierarchical porous graphene aerogels (HGAs) with tunable porous architecture by a “fishing” process with polystyrene (PS) particles as sacrificial templates. Structure and morphology were characterized by X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM), respectively. The 3D HGAs exhibits low density, super hydrophobicity, high porosity and good thermal stability, which were used as adsorbents for removal of oils and organic solvents, showing highly efficient adsorption. In addition, they could be regenerated by heat treatment to release the adsorbates. After eight toluene-adsorbing and drying recycles, the adsorption capacity of HGAs reaches 93% of the initial uptake.