Hello friends....

As we know when we shrunk the size from bulk to nano the bandgap of the material increases......

But when we go from Graphite to Graphene, why there is no change in the bandgap

Views: 136

Reply to This

Replies to This Discussion

Consider H to Zn. The band gap of H is more than that of Zn as Zn tends to have more no. of electrons(electron clouds)surrounding it. So, more electrons means, lesser band gap, as there is an increase in bands between the energy levels. When we see Graphene, it itself is a zero-gap semiconductor. Graphite is nothing but stacks of graphene layer, one over the other. Thus, producing no change in the band gap. 

I hope, this satisfies your query. Thanks!
For more info, please refer to the below link:
http://prb.aps.org/abstract/PRB/v74/i7/e075404

Thank you Madhulika Sinha for replying me.......

As you mentioned here, according to eletron affinity and electronegativity in periodic table the band structure will vary..........But if u consider bulk material...for example Gold (Au).....yellow in color but when we go on reduce the size the bandgap increases in the same way if we go from Stacked graphene to single layered graphene the bandgap should increase but it remains the same......

MADHULIKA SINHA said:

Consider H to Zn. The band gap of H is more than that of Zn as Zn tends to have more no. of electrons(electron clouds)surrounding it. So, more electrons means, lesser band gap, as there is an increase in bands between the energy levels. When we see Graphene, it itself is a zero-gap semiconductor. Graphite is nothing but stacks of graphene layer, one over the other. Thus, producing no change in the band gap. 

I hope, this satisfies your query. Thanks!
For more info, please refer to the below link:
http://prb.aps.org/abstract/PRB/v74/i7/e075404

Dear Sandeep,

As Madhulika mentioned that graphite is nothing but stacked graphene layers in 3D. There is indeed a change in band gap when u go from grahite to graphene but that is very small and not observable owing to very small band gap of graphite. It is mentioned in the reference provided by Madhulika. 

In case of Au, it is the quantum confinement effect which gives rise to different colors due to surface plasmon resonance.

SK

Thank you sir for replying me......

is this the answer which is mentioned in the reference......graphite shows a semimetallic behavior with a band overlap of about 41 meV. In contrast to a single graphene layer, we show that two graphene layers have a parabolic spectrum around the Fermi energy and are a semimetal like graphite; however, the band overlap of 0.16 meV is extremely small....

i.e., from 41 meV to 0.16 meV.......

Dr. Satender Kataria said:

Dear Sandeep,

As Madhulika mentioned that graphite is nothing but stacked graphene layers in 3D. There is indeed a change in band gap when u go from grahite to graphene but that is very small and not observable owing to very small band gap of graphite. It is mentioned in the reference provided by Madhulika. 

In case of Au, it is the quantum confinement effect which gives rise to different colors due to surface plasmon resonance.

SK

Reply to Discussion

RSS

Latest Activity

Profile IconThe International NanoScience Community via Facebook
Facebook8 hours ago · Reply
Profile IconDeepak Kukkar, Anne Nielsen, Dr. Rohit Kumar Mishra and 1 more joined The International NanoScience Community
8 hours ago

Full member
TINC posted a blog post
8 hours ago

Full member
Poonam Sharma updated their profile
15 hours ago

Welcome - about us

Welcome! Nanopaprika was cooked up by Hungarian chemistry PhD student in 2007. The main idea was to create something more personal than the other nano networks already on the Internet. Community is open to everyone from post-doctorial researchers and professors to students everywhere.

There is only one important assumption: you have to be interested in nano!

Nanopaprika is always looking for new partners, if you have any idea, contact me at editor@nanopaprika.eu

Dr. András Paszternák, founder of Nanopaprika

Publications by A. Paszternák:

Smartphone-Based Extension of the Curcumin/Cellophane pH Sensing Method

Pd/Ni Synergestic Activity for Hydrogen Oxidation Reaction in Alkaline Conditions

The potential use of cellophane test strips for the quick determination of food colours

pH and CO2 Sensing by Curcumin-Coloured Cellophane Test Strip

Polymeric Honeycombs Decorated by Nickel Nanoparticles

Directed Deposition of Nickel Nanoparticles Using Self-Assembled Organic Template,

Organometallic deposition of ultrasmooth nanoscale Ni film,

Zigzag-shaped nickel nanowires via organometallic template-free route

Surface analytical characterization of passive iron surface modified by alkyl-phosphonic acid layers

Atomic Force Microscopy Studies of Alkyl-Phosphonate SAMs on Mica

Amorphous iron formation due to low energy heavy ion implantation in evaporated 57Fe thin films

Surface modification of passive iron by alkylphosphonic acid layers

Formation and structure of alkylphosphonic acid layers on passive iron

Structure of the nonionic surfactant triethoxy monooctylether C8E3 adsorbed at the free water surface, as seen from surface tension measurements and Monte Carlo simulations

Next partner events of TINC

We are Media Partner of: