I.The surface atoms constitute a considerable fraction of the total no.of atoms of the nanoparticle

SurfaceVs Bulk species

In a bulk material,

Vol.density is about 10²³ atoms/cm³

surface density is about 10¹⁵ atoms /cm²

For a cube with a side length of 1nm, i.e.10^-7 cm,

The total no.of atoms is 10²³ X (10^-7)³ = 100

No. of surface atoms is 10¹⁵ X (10^-7)² X 6  = 60

Thus, surface to total atoms is 60%

So,surface atoms possess more energy than bulk atoms & hence the surface atoms are chemically more reactive.

Nanomaterials  thus exhibit remarkable reactivity & this can be exploited in a number of ways.

 

 

 

 

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