Sunday 30 September 2012

Quantum confinement in nanoparticles

Quantum confinement in nano particles

Nano technology an emerging technology which has gained fame in every field of life from an excellent sunscreen to an electronic chip.This emerging technology has given excellent properties to even those elements which at one time were thought of being useless  For example Carbon is a non metal but when considered at the nano scale the carbon nano tubes are the best conductors .
But what is the enigma beyond size if this size can make a non conductor an insulator what is the basic physics beyond it .Well the answer is simple and that is Quantum confinement.

The quantum confinement effect is observed when the size of the particle is too small to be comparable to the wavelength of  the electron.To understand this effect we break the words like quantum and confinement, the word confinement means to confine the motion of randomly moving electron to restrict its motion in specific energy levels( discreteness) and quantum  reflects the atomic realm of particles.So as the size of a particle decrease till we a reach a nano scale the decrease in confining dimension makes the energy levels discrete and this increases or widens up the band gap  and ultimately the band gap energy also increases.Since the band gap and wavelength are inversely related to each other the wavelength decrease with decrease in size and the proof is the emission of blue radiation .
Comparison of a bulk material and nano particle reveals that too from the diagram the blue wavelength and the red wavelengthAdd URL Nanotechnology - Science and Technology - Web ... www.directorymix.com/science-and-technology/nanotechnology/