Symmetry-Breaking-Induced Frequency Combs in Graphene Resonators.

Nonlinearities are inherent to the dynamics of two-dimensional materials. Phenomena-like intermodal coupling already arise at amplitudes of only a few nanometers, and a range of unexplored effects still awaits to be harnessed. Here, we demonstrate a route for generating mechanical frequency combs in graphene resonators undergoing symmetry-breaking forces.

Growth of Graphene on a Liquified Copper Skin at Submelting Temperatures.

In chemical vapor deposition of graphene, crossing over the melting temperature of the bulk catalyst is an effective approach to heal the defects and thus improve the crystallinity of the lattice. Here, electromagnetic absorption (the capability of metals to absorb radiated thermal energy) yields a thin skin of liquid metal catalyst at submelting temperatures, allowing the growth of high quality graphene. In fact, a chromium film initially deposited on one side of a copper foil absorbs the thermal energy radiated from a heating stage several times more effectively than a plain copper foil.

Supramolecular Multilayered Templates for Fabricating Nanometer-Precise Spacings: Implications for the Next-Generation of Devices Integrating Nanogap/Nanochannel Components.

Molecular transistors, electromagnetic waveguides, plasmonic devices, and novel generations of nanofluidic channels comprise precisely separated gaps of nanometric and subnanometric spacing. Nonetheless, fabricating a nanogap/nanochannel is a technological challenge, currently tackled by several approaches such as breakdown electromigration and lithography. The aforementioned techniques, though, are limited, respectively, in terms of gap stability and ultimate resolution.

Encapsulation of Graphene in the Hydrophobic Core of a Lipid Bilayer.

Theoretical simulations have predicted that a lipid bilayer forms a stable superstructure when a sheet of graphene is inserted in its hydrophobic core. We experimentally produced for the first time a lipid-graphene-lipid assembly by combining the Langmuir-Blodgett and the Langmuir-Schaefer methods. Graphene is sandwiched and remains flat within the hydrophobic core of the lipid bilayer.

Correction to "Molecular Caging of Graphene with Cyclohexane: Transfer and Electrical Transport".

[This corrects the article DOI: 10.1021/acscentsci.6b00236.

Lateral Non-covalent Clamping of Graphene at the Edges Using a Lipid Scaffold.

Developing a clean handling and transfer process, capable of preserving the integrity of two-dimensional materials, is still a challenge. Here, we present a flexible, dynamic, and lipid-based scaffold that clamps graphene at the edges providing a practical, simple, and clean graphene manipulation and transfer method. Lipid films with different surface pressures are deposited at the air/copper-etchant interface immediately after placing the graphene samples.

Zero-Depth Interfacial Nanopore Capillaries.

High-fidelity analysis of translocating biomolecules through nanopores demands shortening the nanocapillary length to a minimal value. Existing nanopores and capillaries, however, inherit a finite length from the parent membranes. Here, nanocapillaries of zero depth are formed by dissolving two superimposed and crossing metallic nanorods, molded in polymeric slabs.

Water-Dispersible Silica-Coated Upconverting Liposomes: Can a Thin Silica Layer Protect TTA-UC against Oxygen Quenching?

Light upconversion by triplet-triplet annihilation (TTA-UC) in nanoparticles has received considerable attention for bioimaging and light activation of prodrugs. However, the mechanism of TTA-UC is inherently sensitive for quenching by molecular oxygen. A potential oxygen protection strategy is the coating of TTA-UC nanoparticles with a layer of oxygen-impermeable material.

Molecular Caging of Graphene with Cyclohexane: Transfer and Electrical Transport.

Transfer of large, clean, crack- and fold-free graphene sheets is a critical challenge in the field of graphene-based electronic devices. Polymers, conventionally used for transferring two-dimensional materials, irreversibly adsorb yielding a range of unwanted chemical functions and contaminations on the surface. An oil-water interface represents an ideal support for graphene.

Chemistry at the Edge of Graphene.

The selective functionalization of graphene edges is driven by the chemical reactivity of its carbon atoms. The chemical reactivity of an edge, as an interruption of the honeycomb lattice of graphene, differs from the relative inertness of the basal plane. In fact, the unsaturation of the pz orbitals and the break of the π conjugation on an edge increase the energy of the electrons at the edge sites, leading to specific chemical reactivity and electronic properties.

Single molecule detection with graphene and other two-dimensional materials: nanopores and beyond.

Graphene and other two dimensional (2D) materials are currently integrated into nanoscaled devices that may - one day - sequence genomes. The challenge to solve is conceptually straightforward: cut a sheet out of a 2D material and use the edge of the sheet to scan an unfolded biomolecule from head to tail. As the scan proceeds - and because 2D materials are atomically thin - the information provided by the edge might be used to identify different segments - ideally single nucleotides - in the biomolecular strand.