1. Synthesis of Copper Nanoparticles In Nonpolar as Lubricant Additives
Presentation On
Synthesis of Copper Nanoparticles
In Nonpolar
as Lubricant Additives
By:
Dheeraj Kumar
M.Tech
Amity University,
India

2. Metal Nanoparticles in Nonpolar Solvent
As per literature survey, Metal Nanoparticles can be synthesized in Nonpolar solvent by mainly three ways;
Microemulsion Synthesis
Synthesis by Organometal route
Phase Transfer Method

3. Factors for Selecting Synthesis Method
Should be Environmental Friendly
Mass Production should be possible
Less Energy consumption during synthesis
Minimum Steps for synthesis
No Water content in Final Product
Final Product should NOT contain any Byproduct

4. Why Copper Nanoparticles
Copper precursor is easily available in the market; as well as it is cheap as compare to silver or gold precursors
Copper nanoparticles are having good thermal properties, which can be utilize in lubricants for heat dissipation
Copper nanoparticles are having remarkable tribological properties, low hardness leads to reduction in friction; and low elastic modulus reduces the wear

5. Copper Nanoparticles in Nonpolar Solvent
Chemical Required:
Copper Acetate, Sodium Borohydride, Sodium Oleate, Deionized Water, Nonpolar Solvent, H3PO4
Process:
Aqueous solution of Copper Acetate was prepared
Aqueous solution of reducing agent (NaBH4) & capping agent (Sodium Oleate) was prepared
Above solutions were mixed together, which formed Green color; indicates the formation of Copper Nanoparticles
NaBH4
Sodium Oleate
Copper Acetate
In Water
Copper NP
In Water

6. Phase Transfer:
Cyclohexane was added to Copper nanoparticles capped with Sodium Oleate
H3PO4 was added to the above solution; instant color transfer from aqueous to nonpolar solvent was seen
Color transfer into nonpolar solvent indicate the transfer of Nanoparticles into nonpolar solvent from water
Cyclohexane
H3PO4
After 2 days
Copper NP
In Water
Copper NP
In Cyclohexane

7. Mechanism: Weak Acid Nonpolar Solvent Polar Solvent
Reason behind the phase transfer of Nanoparticles from Polar to Nonpolar solvent is; using Surfactant as Capping agent for nanoparticles
Adding the weak acid, give some energy to the surfactant molecule to rearrange into nonpolar solvent to a minimum possible energy state
Weak Acid
Polar Solvent
Nonpolar Solvent

8. Cyclohexane Base Oil (40042) Copper Acetate In Water Copper NP
Phase Transfer
Agent
Capping Agnt
Reducing Agnt
Copper Acetate
In Water
Copper NP
In Water
Phase Transfer
Base Oil (40042)
Agent

9. To Increase concentration in Base Oil (40042)
Phase Transferred in 40042
56ppm
Copper NP in Water
254ppm
Phase Transferred in Cyclohexane
Cyclohexane Mixed with 40042
Cyclohexane Extracted by Rota-vapor
Copper NP in 40042
228ppm

10. UV-Vis Spectroscopy

11. Dynamic Light Scattering
Copper nanoparticles in Cyclohexane
after phase transfer
Copper nanoparticles in 40042
After phase transfer

12. Dynamic Light Scattering
Copper nanoparticles in 40042
After phase transfer
Copper nanoparticles in 40042
Transferred from Cyclohexane

13. Transmission Electron Microscope
TEM images of Copper nanoparticles in Water before phase transfer
Most of the particles are in size range of 2nm to 6nm

14. Transmission Electron Microscope
TEM images of Copper nanoparticles in Cyclohexane
Most of the particles are in size range of 2nm to 7nm

15. Transmission Electron Microscope
Size in nanometer

16. Factors Affecting Synthesis
Copper NP size is effected by concentration of Capping & Reducing agent
Concentration of Copper NP in nonpolar solvent is effected by the viscosity of the nonpolar solvent
On increasing the concentration of Surfactant; web like structure start forming at the water-oil interface
On increasing the stirring; color of both water and oil phase start disappearing

17. Way Forward & Future Aspects
Copper Nanoparticles would be evaluated as additives in commercial lubricants
Silver Nanoparticles would be synthesized by the same route; and evaluated as additives in lubricants
Copper nanoparticles can be used as conductive ink for electronic circuit printing

18. Thank You