Graphene (C(n)) — Properties, Uses & Safety

Overview

Graphene is a two-dimensional allotrope of carbon consisting of a single layer of carbon atoms arranged in a hexagonal honeycomb lattice. Each carbon atom is sp2 hybridized and bonded to three neighbors, with the remaining p-orbital electrons forming a delocalized pi system across the entire sheet. Although graphene's formula is simply written as C(n) since it is an extended structure with no fixed molecular weight, its properties are extraordinary. Graphene is the thinnest material ever measured — just one atom thick — yet it is the strongest material ever tested, with a tensile strength over 100 times greater than steel. It is also an exceptional electrical conductor (electron mobility up to 200,000 cm2/V-s), an excellent thermal conductor, nearly transparent (absorbing only 2.3% of visible light), and remarkably flexible. Graphene was first isolated in 2004 by Andre Geim and Konstantin Novoselov at the University of Manchester using adhesive tape to peel layers from graphite — a deceptively simple technique called mechanical exfoliation that earned them the 2010 Nobel Prize in Physics. At standard conditions, graphene appears as transparent to black sheets depending on the number of layers. It carries no significant GHS hazard codes, though inhalation of graphene nanoparticles is an area of active safety research. Potential applications for graphene span electronics (flexible displays, ultrafast transistors), energy storage (supercapacitors, improved batteries), composite materials, water filtration membranes, and biomedical sensors. For chemistry students, graphene provides an outstanding platform for exploring carbon allotropy, hybridization, delocalized bonding, and the relationship between atomic structure and material properties. Comparing graphene with graphite (stacked graphene layers held by van der Waals forces), diamond (sp3 hybridized), and fullerenes (curved sp2) reinforces how bonding and structure determine properties. Graphene also connects to cutting-edge discussions about nanomaterials, sustainable technology, and the future of materials science.

IUPAC Name

graphene

CAS Number

1034343-98-0

PubChem CID

0

Molecular Formula

C(n)

Molar Mass

0 g/mol

State at STP

solid

Appearance

Transparent to black, one atom thick sheets