X-axis tells you the critical point in first brillouin zone and y axis is the energy. In short it is band structure of the material. It depends on the structure of the material. Both the material shows direct band gap and it exist at A point ( first fig.) and at R point ( second fig). If you can design material in such manner that the band gap can be tuned, then idea is call band gap Engineering ( other thing are also there but on lighter node )
Ba al This image depicts the band structures where energies are referenced with respect to the valence band edge.
X-axis tells you the critical point in first brillouin zone and y axis is the energy. In short it is band structure of the material. It depends on the structure of the material. Both the material shows direct band gap and it exist at A point ( first fig.) and at R point ( second fig). If you can design material in such manner that the band gap can be tuned, then idea is call band gap Engineering ( other thing are also there but on lighter node )
Great read: "Introduction to Solid State Physics" by Charles Kittel. Explains all the concepts you will need to understand band diagrams including crystallography, reciprocal space, and Brillouin zones.
Dear Ba al,
Energy bandgap engineering is the control of the bandgap of the nanomaterial by two methods:
- The first method is that one changes the particulate size of the nanostructure.
As the grain size decreases the bandgap increases.
- The other method is to change the chemical structure of the material.
The figure above as the colleague said show the value and the location of the bhandgap in the energy band structure.
Best wishes
In precise, it means to control the bandgap of the nanostructures by controlling certain properties like
shape,
dimensions,
compositions,
surrounding environment etc.
Here, I am referring optical bandgap.
Regards.
The energy band structure is the crystal structure dependence properties of the material. Since the crystal structue is a size dependent phenomenon in the nanascale size then consequently the electronic energy bads should also changes. For example the energy gap of 1.1eV for a bulk Si will increase to mor than 1.5eV for its nanoparticle of size 3nm and less. The same dependence will occure for other structure energy points. For more information you can see the attached titles;
1-Structure and Thermal properties of Binary Group III2-VI3 Nanoparticlesitle
November 2016
DOI: 10.13140/RG.2.2.16201.75365
Please have other references;
2-Solid Surface and Nanoscale materials Structure
July 2016
DOI: 10.13140/RG.2.2.31947.59684
3-Size Effects on Cohesive Energy, Debye Temperature and Lattice Heat Capacity from First-Principles Calculations of Sn Nanoparticles
December 2017Proceedings of the National Academy of Sciences, India - Section A 88(1)
DOI: 10.1007/s40010-017-0417-y
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science
- Materials
- Nanomaterials