Surface to Volume Ratio of Nano materials!
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This is a video created
This is a video created by my student Mohit during his final year of graduation. It explains the concept of #Surface_to_volume_ratio of nano materials in a simple way.
#Surface_area_to_volume_ratio in #nano particles have a significant effect on the nano particles #properties. Firstly, nano particles have a relatively larger surface area when compared to the same volume of the material. For example, let us consider a sphere of radius r:
The surface area of the sphere will be 4πr2
The volume of the sphere = 4/3(πr3)
Therefore the surface area to the volume ratio will be 4πr2/{4/3(πr3)} = 3/r
It means that the surface area to volume ration increases with the decrease in radius of the sphere and vice versa. It can also be conclude here that when given volume is divided into smaller piece, the surface area increases. Therefore as particle size decreases, a greater portion of the atoms are found at the surface compared to those inside. For example, a particle of size 3 nm has 50% of its atoms on its surface, at 10 nm 20% of its atoms and at 30 nm has 5% of its atoms on its surface. Therefore nano particles have a much greater surface area per unit volume compared with the larger particles. It leads to nano particles more chemically reactive. As growth and catalytic chemical reaction occurs at surfaces, therefore a given mass of nano material will be much more reactive than the same mass of material made up of large particles. It is also found that materials which are inert in their bulk form are reactive when produced in their nano scale form. It can improve their properties.
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