Nonzero Gap Two-Dimensional Carbon Allotrope from Porous Graphene

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A nonzero gap two-dimensional carbon allotrope from porous graphene

Graphene has been one of the hottest topics in materials science in the last years. Because of its special electronic properties graphene is considered one of the most promising materials for future electronics. However, in its pristine form graphene is a gapless semiconductor, which poses some limitations to its use in some transistor electronics. Many approaches have been tried to create, in a controlled way, a gap in graphene. These approaches have obtained limited successes. Recently, hydrogenated graphene-like structures, the so-called porous graphene, have been synthesized. In this work we show, based on ab initio quantum molecular dynamics calculations, that porous graphene dehydrogenation can lead to a spontaneous formation of a nonzero gap two-dimensional carbon allotrope, called biphenylene carbon (BC). Besides exhibiting an intrinsic nonzero gap value, BC also presents well delocalized frontier orbitals, suggestive of a structure with high electronic mobility. Possible synthetic routes to obtain BC from porous graphene are addressed. © 2012 Materials Research Society.

Graphene to fluorographene and fluorographane: A theoretical study

We report here a fully reactive molecular dynamics study on the structural and dynamical aspects of the fluorination of graphene membranes (fluorographene). Our results show that fluorination tends to produce defective areas on the graphene membranes with significant distortions of carbon-carbon bonds. Depending on the amount of incorporated fluorine atoms, large membrane holes were observed due to carbon atom losses. These results may explain the broad distribution of the structural lattice parameter values experimentally observed. We have also investigated the effects of mixing hydrogen and fluorine atoms on the graphene functionalization. Our results show that, when in small amounts, the presence of hydrogen atoms produces a significant decrease in the rate of fluorine incorporation onto the membrane. On the other hand, when fluorine is the minority element, it produces a significant catalytic effect on the rate of hydrogen incorporation. We have also observed the spontaneous formation of new hybrid structures with different stable configurations (chair-like, zigzag-like and boat-like) which we named fluorographane. © 2013 IOP Publishing Ltd.

Reduced graphene oxide multilayers for gas and liquid phases chemical sensing

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Electronic transport in patterned graphene nanoroads

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Graphene sheet versus two-dimensional electron gas: A relativistic Fano spin filter via STM and AFM tips

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Tailoring Thermal Transport Property of Graphene through Oxygen Functionalization

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

DEVELOPMENT OF A BIOMIMETIC SENSOR MODIFIED WITH HEMIN AND GRAPHENE OXIDE FOR MONITORING OF CARBOFURAN IN FOOD

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determination of carbofuran and diuron in FIA system using electrochemical sensor modified with organometallic complexes and graphene oxide

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Optical spectrum of bottom-up graphene nanoribbons: towards efficient atom-thick excitonic solar cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Simultaneous determination of epinephrine and dopamine by electrochemical reduction on the hybrid material SiO2/graphene oxide decorated with Ag nanoparticles

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hybridization effects on the out-of-plane electron tunneling properties of monolayers: is h-BN more conductive than graphene?

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of inter-adatoms correlations on the local density of states of graphene

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

An Informatics Technical Note on Interaction of DNA - Graphene Chemical Sensor System as Reaction-Diffusion Wave-Based Computing System in Ionised Gaseous environments and their Applications Using Theoretical Studies and Scientific Computation Overview

The physics of plasmas encompasses basic problems from the universe and has assured us of promises in diverse applications to be implemented in a wider range of scientific and engineering domains, linked to most of the evolved and evolving fundamental problems. Substantial part of this domain could be described by R–D mechanisms involving two or more species (reaction–diffusion mechanisms). These could further account for the simultaneous non-linear effects of heating, diffusion and other related losses. We mention here that in laboratory scale experiments, a suitable combination of these processes is of vital importance and very much decisive to investigate and compute the net behaviour of plasmas under consideration. Plasmas are being used in the revolution of information processing, so we considered in this technical note a simple framework to discuss and pave the way for better formalisms and Informatics, dealing with diverse domains of science and technologies. The challenging and fascinating aspects of plasma physics is that it requires a great deal of insight in formulating the relevant design problems, which in turn require ingenuity and flexibility in choosing a particular set of mathematical (and/or experimental) tools to implement them.

Capacitive DNA detection driven by electronic charge fluctuations in a graphene nanopore

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)