Sunday, January 27, 2013

Multifunctional crumpled and folded graphene !

In a recent report in Nature, researchers have demonstrated controlled crumpling and folding of CVD graphene for utilization in various electronics, biomedical, energy and composite applications. 
The approach is very simple and effective.

Pure bulk valley current in graphene !

A scheme for generating large valley currents in graphene mechanical resonators in the suspended regions is reported. 
The work is a progress towards utilizing the valleytronics of graphene.

Spin gating of graphene by proximity effects

Frist principle calculations studies has revealed the significance of proximity effects of a magnetic insulator, europium oxide, on graphene spin related properties. Large spin polarization around 24 % and exchange-splitting band gap around 36 meV are reported.

Thursday, January 24, 2013

Graphene plasmonics helps in detecting drug cheaters!

Another breakthrough from the "Noble winners of graphene discovery" can help in beating the drug cheaters.  Based on reversible hydrogenation of graphene, scientists create a plasmonic metamaterial which has potential for label free biosensing.

Graphene oxide goes for radioactive nuclides!

Graphene oxide, a derivative of graphene, is found to have potential to capture some of the human made radiactive nuclides from sea water.
This is a great breakthrough !

Wednesday, January 23, 2013

Graphene project wins European funds !

Given graphene's unlimited applications, it is not surprising that a graphene project has won European funds in billion. The application sought will be batteries, sensors and computing.

Tuesday, January 22, 2013

Health risks of graphene

Given its wide applications, graphene will be used extensively and is definitely going to be a part of our ecosystem. Therefore, it is mandatory to understand the health risks of graphene for a precaution. 
In a current review article, possible health risks of graphene associated with its shape, size and structures are provided.

Graphene a super gas barrier !

Super gas barrier thin films, fabricated with layer-by-layer assembly of polyethylenimine and graphene oxide, exhibit significantly reduced oxygen and carbon dioxide transmission rates. This thin film's nanobrick wall structure also provides high gas selectivity for hydrogen.

Sunday, January 20, 2013

Dirac Fermions in graphene do a lot- Ratchet effect !

In a recent Nature article, researchers have demonstrated magnetic ratchet effect in graphene under the application of THz radiation which results in transformation of a.c. power to dc currents. 
Sounds interesting !

Tuesday, January 15, 2013

Plasmon transport in graphene

We have heard of charge transport of graphene and its control by external electrical biasing. In a recent work published in Nature Communications, a charge pulse travelling in plasmon mode in graphene to the GHz range can be modulated by applying an external magnetic field. The study paves way for further plasmonic applications of graphene in a controlled manner.

Graphene can be band-engineered for photonic appliations !

In a new published research, complete or quasi collapse of conduction and valence quasi bands of ac-driven graphene is demonstrated using optical waveguides.

I still need to go through the article :-)

CVD graphene as a biosensing platform

In a recent work, reserachers have used Hall measurements to understand the interaction of DNA with graphene to gain further insights in the process. This brings a step forward in using graphene as a bio-sensor for biological applications.

Sunday, January 13, 2013

Micro-wave-chemical vapor deposition of graphene walls

Microwave plasma CVD is used to grow vertically standing graphene walls which can be utilised as field emitters. The technique holds promise to grow graphene at low temperatures.

Sunday, January 6, 2013

Nanoscale Radiative Heat Flow due to Surface Plasmons in Graphene and Doped Silicon

Owing to its two-dimensional electronic structure, graphene exhibits many unique properties. One of them is a wave vector and temperature dependent plasmon in the infrared range. Theory predicts that due to these plasmons, graphene can be used as a universal material to enhance nanoscale radiative heat exchange for any dielectric substrate. Here we report on radiative heat transfer experiments between SiC and a SiO2 sphere that have nonmatching phonon polariton frequencies, and thus only weakly exchange heat in near field. We observed that the heat flux contribution of graphene epitaxially grown on SiC dominates at short distances. The influence of plasmons on radiative heat transfer is further supported with measurements for doped silicon. These results highlight graphene’s strong potential in photonic near field and energy conversion devices.

Carrier Drift Velocity and Edge Magnetoplasmons in Graphene

In a fundamental study using exfoliated graphene, the researchers investigate electron dynamics at graphene edge by studying the propagation of collective edge magnetoplasmon excitations.

Electrical Control of Silicon Photonic Crystal Cavity by Graphene

Efficient conversion of electrical signal to optical signal in nano-photonics enables solid state integration of electronics and photonics. In a recent work, cavity resonance of a Si photonic crystal cavity covered by graphene is significantly changed.

Thursday, January 3, 2013

Vertical field effect transistor based on graphene-WS2 heterostructures

It is well demonstrated that graphene, a 2D atom thick sheet, has the potentials to bring revolution in electronic industry. With the development of other 2D materials like h-BN and transistion metal dichalcogenides like MoS2, WS2, the graphene applications can be truly realized.  
Taking another leap in this direction, researchers have demonstrated a flexible vertical field effect transistor based on graphene-WS2-h BN heterostructures which is a proof of concept device.

Tuesday, January 1, 2013

3D freestanding graphene-MnO2 composite for supercapacitor applications

CVD grown graphene on Ni foam yields a nice 3D graphene network. Researchers have loaded this structure with MnO2 and converted it into an active material  for supercapacitor applications.

Band gap engineered CVD graphene

We have successfully opened up band gap in CVD grown graphene by in-situ BN doping. A band gap of around 0.6 eV is opened. The present work paves way for graphene based technology where band gap is needed.