Three-dimensional cross-linking composite of graphene, carbon nanotubes and Si nanoparticles for lithium ion battery anode.

Various graphene-based Si nanocomposites have been reported to improve the performance of active materials in Li-ion batteries. However, these candidates still yield severe capacity fading due to the electrical disconnection and fractures caused by the huge volume changes over extended cycles. Therefore, we have designed a novel three-dimensional cross-linked graphene and single-wall carbon nanotube structure to encapsulate the Si nanoparticles.

Controllable Edge Oxidation and Bubbling Exfoliation Enable the Fabrication of High Quality Water Dispersible Graphene.

Despite significant progresses made on mass production of chemically exfoliated graphene, the quality, cost and environmental friendliness remain major challenges for its market penetration. Here, we present a fast and green exfoliation strategy for large scale production of high quality water dispersible few layer graphene through a controllable edge oxidation and localized gas bubbling process. Mild edge oxidation guarantees that the pristine sp lattice is largely intact and the edges are functionalized with hydrophilic groups, giving rise to high conductivity and good water dispersibility at the same time.

A New Graphene Derivative: Hydroxylated Graphene with Excellent Biocompatibility.

Graphene derivatives (such as graphene oxide and hydrogenated graphene) have been widely investigated because of their excellent properties. Here, we report large-scale (kilogram scale) synthesis of a new unique graphene derivative: hydroxylated graphene (G-OH). The exclusive existence form of oxygen-containing groups in G-OH is hydroxyl, which was verified by spectral characterization and quantitative halogenating reaction.

Urea-assisted aqueous exfoliation of graphite for obtaining high-quality graphene.

Urea-assisted aqueous exfoliation of graphite was found to be more efficient than exfoliation in N,N-dimethylformamide (DMF), and high-quality graphene was obtained with a yield up to 2.4%. The mechanism in which a primary amine facilitates aqueous exfoliation was proposed and experimentally validated, which may inspire new strategies for efficient liquid exfoliation.