As a potential precursor for the scalable production of graphene, graphene oxide (GO) is of great importance, which can be prepared by the classical Hummers method. However, it is not only troublesome for separating and purifying GO from the obtained mixed liquor but also technically difficult to avoid the agglomeration of individual graphene sheets during the subsequent reduction process. In this paper, we introduce a novel design concept for fabricating 3D graphene (3D-rGO) directly from the GO mixed liquor with the assistant of sulphates. By using an artful anti-solvent precipitation method, sulphates (Na₂SO₄ and the impurities) are firstly generated on the surface of GO nanosheets, which are then removed by simple water-washing at the end of the synthesis. The choice of this method in the fabrication of rGO is motivated by the water-soluble nature of Na₂SO₄, which circumvents the intrinsic problems associated with the prevailing methods for GO separation, purification and reduction, making our approach green, highly efficient and cost-effective. The overall microstructure and phase evolutions of the samples at each step are observed and the formation mechanism of the rGO layers is also proposed. When evaluated as an anode material for Li-ion batteries, the obtained 3D-rGO exhibits the excellent electrochemical properties. The present approach inspires a new way for the fabrication of rGO powder on a large scale.