Graphene
(/ˈɡræf.iːn/) is an allotrope of carbon in the form of a two-dimensional,
atomic-scale, hexagonal lattice in which one atom forms each vertex. It is the
basic structural element of other allotropes, including graphite, charcoal,
carbon nanotubes and fullerenes. It can be considered as an indefinitely large
aromatic molecule, the ultimate case of the family of flat polycyclic aromatic
hydrocarbons.
Graphene
has many unusual properties. It is about 200 times stronger than the strongest
steel. It efficiently conducts heat and electricity and is nearly transparent. Graphene
shows a large and nonlinear diamagnetism, greater than graphite and can be
levitated by neodymium magnets.
Scientists
have theorized about graphene for years. It has unintentionally been produced
in small quantities for centuries, through the use of pencils and other similar
graphite applications. It was originally observed in electron microscopes in
1962, but it was studied only while supported on metal surfaces. The material
was later rediscovered, isolated, and characterized in 2004 by Andre Geim and
Konstantin Novoselov at the University of Manchester. Research was informed by
existing theoretical descriptions of its composition, structure, and properties.
This work resulted in the two winning the Nobel Prize in Physics in 2010
"for groundbreaking experiments regarding the two-dimensional material
graphene."
The
global market for graphene reached $9 million by 2012 with most sales in the
semiconductor, electronics, battery energy, and composites industries. The
rapid and successful development of the research on graphene and graphene-based
nanostructures has been substantially enlarged to include many other
two-dimensional hexagonal semiconductors (THS): phosphorene, silicene,
germanene, hexagonal boron nitride (h-BN) and transition metal dichalcogenides
(TMDCs) such as MoS2, MoSe2, WS2, WSe2 as well as the van der Waals
heterostructures of various THSs (including graphene).
The
present article is a review of recent works on THSs beyond graphene and van der
Waals heterostructures composed of different pairs of all THSs.
One
among the priorities of new THSs compared to graphene is the presence of a
non-vanishing energy bandgap which opened up the ability to fabricate a large
number of electronic, optoelectronic and photonic devices on the basis of these
new materials and their van der Waals heterostructures.
Moreover,
a significant progress in the research on TMDCs was the discovery of valley
degree of freedom.
The
results of research on valley degree of freedom and the development of a new
technology based on valley degree of freedom-valleytronics are also presented.
Thus the scientific contents of the basic research and practical applications
os THSs are very rich and extremely promising.
Title:
| Two-dimensional hexagonal semiconductors beyond graphene | |
| Authors: | Nguyen, B.H. Nguyen, V.H. |
| Keywords: | Graphene Phosphorene Silicene Transition metal dichalcogemides van der Waals heterostructures |
| Issue Date: | 2016 |
| Publisher: | Institute of Physics Publishing |
| Citation: | Scopus |
| Abstract: | The rapid and successful development of the research on graphene and graphene-based nanostructures has been substantially enlarged to include many other two-dimensional hexagonal semiconductors (THS): phosphorene, silicene, germanene, hexagonal boron nitride (h-BN) and transition metal dichalcogenides (TMDCs) such as MoS2, MoSe2, WS2, WSe2 as well as the van der Waals heterostructures of various THSs (including graphene). The present article is a review of recent works on THSs beyond graphene and van der Waals heterostructures composed of different pairs of all THSs. One among the priorities of new THSs compared to graphene is the presence of a non-vanishing energy bandgap which opened up the ability to fabricate a large number of electronic, optoelectronic and photonic devices on the basis of these new materials and their van der Waals heterostructures. Moreover, a significant progress in the research on TMDCs was the discovery of valley degree of freedom. The results of research on valley degree of freedom and the development of a new technology based on valley degree of freedom-valleytronics are also presented. Thus the scientific contents of the basic research and practical applications os THSs are very rich and extremely promising. |
| Description: | Advances in Natural Sciences: Nanoscience and Nanotechnology Volume 7, Issue 4, December 2016, Article number 043001 |
| URI: | http://iopscience.iop.org/article/10.1088/2043-6262/7/4/043001/meta;jsessionid=7D4BF8DAD276BC8CC4675F747037DE05.ip-10-40-1-105 http://repository.vnu.edu.vn/handle/VNU_123/34082 |
| ISSN: | 20436262 |
| Appears in Collections: | Bài báo của ĐHQGHN trong Scopus |
Nhận xét
Đăng nhận xét