Using Reverse Micelle and Hydrothermal Techniques, we created a variety of Nanocrystals, Nanorods, Quatum dots etc. in our Laboratory at DAVIET, Jallandhar ( 2008-2011).

1. Our Chemical Route to
Nanotechnology: An Overview
H. S. Virk1 & Poonam Sharma2
1
Nanotechnology Laboratory, DAV
University, Jalandhar-144008, India
2
Department of Chemistry, St. Francis
Xavier University, Nova Scotia, Canada

2. Routes to Nanotechnology
• Physical, chemical, biological and nature’s self
assembly.
• Top-down and bottom-up approaches.
• Chemical route to nanotechnology is simpler,
cheaper and allows fabrication at bench top
conditions.
• Reverse micelles (microemulsions route) is a
versatile method to produce a variety of
nanoparticles.

3. Bottom Up Techniques Used
• Reverse micelles, co-precipitation, solvothermal, sol-gel and seed growth technique.
• Quantum dots, nanorods and nanoneedles of
Barium Carbonate, Barium Oxalate, Iron
Oxalate, Barium hexaferrite, Zinc Oxide,
Cadmium Sulphide, Cadmium Oxide and Silver
prepared for characterization using SEM, TEM,
UV-Vis, FTIR, XRD, TGA & VSM techniques.

4. Reverse Micelle Schematic

5. Nanoparticle Synthesis (ME route)

6. SEM image of Barium Carbonate
Nanorods

7. TEM images of Barium Carbonate
Nanorods

8. TEM images of Iron Oxalate and
Barium Oxalate Nanocrystals

9. TEM image of CdO Quantum Dots

10. Conversion of Quantum Dots of
CdO to Nanorods using EDA

11. CdS Nanocrystals(CTAB+n-butanol)

12. CdS Nanoneedles(CTAB+nhexanol)

13. CdS Quantum Dots( molar ratio=5)

14. CdS Nanorods (molar ratio=15)

15. Ba-M Hexaferrite Crystals (ME)

16. Ba-M Hexaferrite Crystals (CP)

17. Ba-hexaferrite ME(after
calcination)

18. Ba-hexaferrite CP(after calcination)

19. Hysteresis loops of Ba-hexaferrite
nanoparticles (CP & ME samples)

20. SEM image of ZnO Nanocrystals in
Ethanol and Nanorod(adding EDA)

21. TEM image of Ag quantum dots
and embedded nano particles

22. Electrochemical Synthesis
• Electrochemistry has been used to fabricate
nanowires and heterojunctions of Cu, Cu-Se
and Cd-S. The results of our investigations can
be exploited for fabrication of nanodevices for
application in opto-electronics and nanoelectronics. During failure of our Experiments,
exotic patterns (nanoflowers, nanocrystals,
nanobuds) were produced under nature’s self
assembly.

23. Electrolytic Cell

24. Electrodeposition of Nanowires
• The electrolyte used is CuSO4.5H2O acidic
solution. The rate of deposition depends
upon
current
density,
inter-electrode
distance,
cell
voltage,
electrolyte
concentration and temperature etc. The
technique has been tested for growth of
nanowires of Copper and heterojunctions of
Cu-Se and Cd-S electrochemically using anodic
alumina and polymer templates (Nuclepore
Filters).

25. Atomic Force Microscope(NT-MDT)

26. AFM image of hexagonal pores of
Anodic Alumina Membrane (AAM)

27. SEM Images of Cu Nanowires using
Electrodeposition Technique

28. Capping Effect of Current Variation

29. Copper Lillies grown due to overdeposition of Copper in AAM

30. Copper Nanoflowers grown in
Polymer Template (100nm pores)

31. Copper Marigold (Gainda) Flower

32. A Garden of Copper Nanoflowers

33. SEM micrograph of Nanocrystals of
Polycrystalline Copper

34. 10
20
30
40
50
Position [°2Theta] (Copper (Cu))
60
7 4.29 9 [ °]
6 4.80 9 [ ° ]
KK1
5 0.58 0 [ ° ]
Counts
54 .3 04 [ ° ]
5 4.95 6 [ ° ]
48 .9 20 [ ° ]
45 .448 [ ° ]
43 .4 61 [ ° ]
38.2 83 [ °]
3 6.63 7 [ ° ]
XRD Spectrum of polycrystalline
Copper nanocrystals
60000
40000
20000
0
70

35. XRD spectrum of Cu nanowires
Counts
Cu polycrystalline
1600
400
0
30
40
50
60
70
Position [°2Theta] (Copper (Cu))
80
90

36. SEM Image of CdS Nanowires

37. HRTEM image showing CdS
Nanowire & Heterojunctions

38. I-V plot of CdS Nanowire arrays
showing RTD characteristics

39. SEM image of Cu-Se Nanowires

40. Cu-Se nanowires exhibit p-n
junction diode characteristics

41. Thank
You !!!