Graphene nanosheets (GNSs) possess outstanding conductivity, good thermal and chemical stabilities and desirable mechanical strengths. However, the unfunctionalized GNSs are hydrophobic and insoluble in water, which limits their application in many technological areas. Herein, we report a design strategy to exfoliate few-layered aqueous dispersible graphene by a simple ball-milling technique. The modifier of sodium lignosulfonate (LS) enables to synthesize LS-decorated GNSs from natural graphite based on the strong π–π interaction, greatly improving GNSs dispersion in water. The resultant GNSs exhibit a high production yield (∼100%), high dispersion concentration and excellent film formation ability. The electrical and thermal conductivities of the as-prepared graphene paper were up to 2385 S cm⁻¹ and 1324 W m⁻¹ K⁻¹, respectively, superior to those of most previously reported graphene materials. This graphene paper with the superb electrical and thermal conduction properties also exhibits excellent mechanical flexibility and structure intensity during bending, which has potential usages in electronic packaging and high power thermal management.

Graphene-based films are widely used in the electronics industry. Here, surface hydroxylated graphene sheets (HGS) have been synthesized from natural graphite (NG) by a rapid and efficient molten hydroxide-assisted exfoliation technique. This method enables preparation of aqueous dispersible graphene sheets with a high dispersed concentration (∼10.0 mg ml ⁻¹ ) and an extraordinary production yield (∼100%). The HGS dispersion was processed into graphene flexible film (HGCF) through fast filtration, annealing treatment and mechanical compression. The HGS endows graphene flexible film with a high electrical conductivity of 11.5 × 10 ⁴ S m ⁻¹ and a superior thermal conductivity of 1842 W m ⁻¹ K ⁻¹ . Simultaneously, the superflexible HGCF could endure 3000 repeated cycles of bending or folding. As a result, this graphene flexible film is expected to be integrated into electronic packaging and high-power electronics applications.

Graphene shows great promise for advanced filtration membranes with high permeance and enhanced rejection. Here we demonstrate filtration membranes with a nanochannel network for superior separation performance using 100–500 nm-wide graphene nanoplatelets (GnPs) that are efficiently prepared via a green method. The resulting membranes exhibit a well packed layer structure formed by GnPs and are highly stable in water and organic solvents and even in strongly acidic and alkaline media. Moreover, the GnP membranes possess high fluxes and good selectivity in both water and organic solvents based on the small size nanoplatelets and the stable nanochannels between the GnPs. The exfoliated GnPs and the subsequent membranes show great potential for practical applications in water purification and organic solvent filtration.

Correction for ‘An ultrahigh thermal conductive graphene flexible paper’ by Jiheng Ding et al., Nanoscale, 2017, 9, 16871–16878, DOI: 10.1039/C7NR06667H.