Are you an EPFL student looking for a semester project?
Work with us on data science and visualisation projects, and deploy your project as an app on top of GraphSearch.
Concept
Graphene
Summary
Graphene (ˈgræfiːn) is an allotrope of carbon consisting of a single layer of atoms arranged in a hexagonal lattice nanostructure. The name is derived from "graphite" and the suffix -ene, reflecting the fact that the graphite allotrope of carbon contains numerous double bonds.
Each atom in a graphene sheet is connected to its three nearest neighbors by σ-bonds and a delocalised π-bond, which contributes to a valence band that extends over the whole sheet. This is the same type of bonding seen in carbon nanotubes and polycyclic aromatic hydrocarbons, and (partially) in fullerenes and glassy carbon. The valence band is touched by a conduction band, making graphene a semimetal with unusual electronic properties that are best described by theories for massless relativistic particles. Charge carriers in graphene show linear, rather than quadratic, dependence of energy on momentum, and field-effect transistors with graphene can be made that show bipolar conduction. Charge transport is ballistic over long distances; the material exhibits large quantum oscillations and large and nonlinear diamagnetism. Graphene conducts heat and electricity very efficiently along its plane. The material strongly absorbs light of all visible wavelengths, which accounts for the black color of graphite; yet a single graphene sheet is nearly transparent because of its extreme thinness. The material is about 100 times as strong as would be the strongest steel of the same thickness.
Scientists theorized the potential existence and production of graphene for decades. It has likely been unknowingly produced in small quantities for centuries, through the use of pencils and other similar applications of graphite. It was possibly observed in electron microscopes in 1962, but studied only while supported on metal surfaces.
In 2004, the material was rediscovered, isolated and investigated at the University of Manchester, by Andre Geim and Konstantin Novoselov. In 2010, Geim and Novoselov were awarded the Nobel Prize in Physics for their "groundbreaking experiments regarding the two-dimensional material graphene".
Official source
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related publications (268)
Electronic transport in graphene nanoribbon junctions
Graphene nanoribbons (GNRs) - one-dimensional strips of graphene - share many of the exciting properties of graphene, such as ballistic transport over micron dimensions, strength and flexibility, but
EPFL2022Mass transport of water vapor and ions from Å-scale graphene nanopores
Hydrodynamics at the nanoscale involves both fundamental study and application of fluid and mass transport phenomena in nanometer-sized confinements. Nanopores in single-layer graphene can be highly a
EPFL2022Transfer of Graphene under Ultra-High Vacuum
This thesis reports on a novel method for graphene transfer that is fully UHV compatible, which has remained a challenge for a long time due to the necessity of supporting graphene for transfer and mo
EPFL2022Related people (91)
Related units (16)
Related concepts (158)
Nanoparticle
A nanoparticle or ultrafine particle is usually defined as a particle of matter that is between 1 and 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 100 nm in only two directions. At the lowest range, metal particles smaller than 1 nm are usually called atom clusters instead.
Superlubricity
In physics (specifically tribology), superlubricity is a regime of motion in which friction vanishes or very nearly vanishes. What is a "vanishing" friction level is not clear, which makes the term quite vague. As an ad hoc definition, a kinetic coefficient of friction less than 0.01 can be adopted. This definition also requires further discussion and clarification. Superlubricity may occur when two crystalline surfaces slide over each other in dry incommensurate contact.
Allotropes of carbon
Carbon is capable of forming many allotropes (structurally different forms of the same element) due to its valency. Well-known forms of carbon include diamond and graphite. In recent decades, many more allotropes have been discovered and researched, including ball shapes such as buckminsterfullerene and sheets such as graphene. Larger-scale structures of carbon include nanotubes, nanobuds and nanoribbons. Other unusual forms of carbon exist at very high temperatures or extreme pressures.
Related courses (49)
EE-567: Semiconductor devices II
Students will learn about understanding the fundamentals and applications of emerging nanoscale devices, materials and concepts.
Remark: at least 5 students should be enrolled for the course to be g
PHYS-756: Lectures on twisted bilayer graphene
Twisted Bilayer Graphene (TBG) is a change of paradigm in condensed matter: with flat topologic bands, it provides a platform for unconventional superconductivity, correlated insulation, Plankian meta
PHYS-627: Magnetic and semiconducting nanostructures
Introduce students to the magnetic and electronic properties of nanostructures
Related lectures (215)
Excitonic Devices: Manipulation and Applications
Explores exciton manipulation in devices and their potential applications for low-power computing and optoelectronic components.
Density Functional Theory and Tight-Binding Models
Explores modeling multilayer 2D materials, tight-binding models, and electrical conductivity in materials, emphasizing the importance of symmetries and reduced models.
Spin-Wave Dynamics in CoZnMn: Experiments and Results
Explores spin-wave dynamics in CoZnMn, emphasizing morphology impact and experimental results.