Experiment No-
Synthesis of Nanoparticles
1. Aim: Synthesis of Copper nanoparticles.
2. Objectives:
1.
2.
3.
4.
To understand the concept nanomaterials.
To prepare solution.
To differentiate between top-down and bottom-up approach for synthesis of nanoparticles.
To identify scattering of light.
3. Theory:
Synthesis of nanomaterials (material having size 1 to 100 nm) can be done by various ways these
methods are divided as Bottom up & Top down. There are two methods of preparing nanomaterials. One is
top-down approach & the other is bottom-up approach. In top-down approach, the material is reduced
from bulk size to nano scale. Examples for top-down approach are ball milling method & nanolithography.
In bottom-up approach, matter in atomic or molecular level gets assembled to form tiny clusters which
grow to reach nano-size. Examples for bottom-up approach are arc discharge method, chemical vapor
deposition, physical vapor deposition & sol gel method.
4. Apparatus: Digital weight box, measuring cylinder.
5. Chemicals: Copper Sulphate, ascorbic acid, distilled water etc.
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6. Procedure:
1.
2.
3.
4.
5.
Dissolve 2 gm Copper Sulphate in distilled water stir well to obtain clear solution.
Heat Copper Sulphate solution until it boils.
Dissolve 4 gm ascorbic acid in 10 ml water.
Add ascorbic acid solution dropwise to Copper Sulphate solution with constant stirring at 60 OC.
After completion of reaction the copper nanoparticles will be get settled at the bottom.
7. Chemical reaction
8. Key observations
1) The pH of the solution should be measured both before and after the reaction.
Sr. No.
i.
ii.
Place blue litmus paper in
Solution of Ascorbic acid
Solution containing both
ascorbic acid and Copper
Sulphate solution
Change in color of litmus Conclusion
paper
Yes
Solution is acidic
Yes
Solution is acidic
2. Light Scattering
Sr. No.
i.
ii.
Direct the laser light
Path is visible/Path is not Conclusion
visible
Copper Sulphate solution
No
Clear solution
Solution containing both
Solution is colloidal due
ascorbic acid and silver
Yes
to formation of Copper
nitrate (Slightly shake)
nanoparticles
8. Result:
i.
ii.
Copper nanoparticles are prepared by using …………………………..approach.
Nanoparticles …………………………beam of light.
9. Questions:
1. State properties of nanoparticles.
2. What is scattering of light.
3. Find more methods based on Bottom-up & Top-down approach used to obtain nanoparticle.
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