Graphene exhibits unusual electronic properties, caused by a linear band structure near the Dirac point. This band structure is determined by the stacking sequence in graphene multilayers. Here we present a novel method of microscopically controlling the band structure. This is achieved by epitaxy of graphene on 3C-SiC(111) and 3C-SiC(100) thin films grown on a 3D microfabricated Si(100) substr...

Graphene and its composite hydrogels with interconnected three-dimensional (3D) structure have raised continuous attention in energy storage. Herein, we describe a simple hydrothermal strategy to synthesize 3D CoS/graphene composite hydrogel (CGH), which contains the reduction of GO sheets and anchoring of CoS nanoparticles on graphene sheets. The formed special 3D structure endows this composi...

In this study, three-dimensional (3D) graphene assemblies are prepared from graphene oxide (GO) by a facile in situ reduction-assembly method, using a novel, low-cost, and environment-friendly reducing medium which is a combination of oxalic acid (OA) and sodium iodide (NaI). It is demonstrated that the combination of a reducing acid, OA, and NaI is indispensable for effective reduction of GO i...

Graphene family materials, including graphene quantum dots (GQDs), graphene nanoribbons (GNRs) and 3D graphene (3D-G), have attracted much research interest for the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries, due to their unique structural characteristics, such as abundant activate sites, edge effects and the interconnected network. In this review, we summarize recent...

In this study PtFeCo ternary alloys nanoparticles of three dimentional (3D) rhombus shapes dispersed on graphene nanosheets (PtFeCo/Gr) were successfully prepared and studied as electrocatalysts for oxygen reduction reaction (ORR) in polymer-electrolyte fuel cells. A combination of analytical techniques including powder X-ray diffraction, X-ray photoelectron spectra, inductively coupled plasma-...

In this study, we presented a droplet-based microfluidic system for synthesizing three-dimensional (3D) graphene structure, called graphene popcorn. The droplets that were obtained by varying the flow rates and the concentration of graphene oxide (GO) solution were incubated in the furnace for rapid evaporation, resulting in the reduction of the GO as well as the aggregation of GO to form the g...

In this report, we succeed in constructing a hybrid three-dimensional (3D) nanocomposite film by alternatively assembling the graphene nanosheets modified by ionic liquid (IL) and Pt nanoparticles (Pt NPs). In this strategy, an imidazolium salt-based ionic liquid (IS-IL)-functionalized graphene was synthesized by covalently binding 1-(3-aminopropyl)-3-methylimidazolium bromide onto graphene nan...

Low-density nanostructured foams are often limited in applications due to their low mechanical and thermal stabilities. Here we report an approach of building the structural units of three-dimensional (3D) foams using hybrid two-dimensional (2D) atomic layers made of stacked graphene oxide layers reinforced with conformal hexagonal boron nitride (h-BN) platelets. The ultra-low density (1/400 ti...

Porous graphene nanostructures are of great interest for applications in catalysis and energy storage. However, the fabrication of three-dimensional (3D) macroporous graphene nanostructures with controlled morphology, porosity and surface area still presents significant challenges. Here we introduce an ice-templated self-assembly approach for the integration of two-dimensional graphene nanoshee...