In situ observation of colloidal monolayer nucleation driven by an alternating electric field


The nucleation of crystalline materials is a hotly debated subject in the physical sciences1. Despite the emergence of several theories in recent decades2,3,4,5,6,7, much confusion still surrounds the dynamic processes of nucleation5,6,7. This has been due in part to the limitations of existing experimental evidence. Charged colloidal suspensions have been used as experimental model systems for the study of crystal nucleation and structural phase transitions8,9,10,11,12, as their crystallization phase diagram is analogous to that of atomic and molecular systems, but they can be visualized using microscopy. Previously, three-dimensional imaging of colloidal nucleation dynamics was achieved using confocal microscopy13. However, the limited temporal resolution of the confocal microscope is of concern when trying to capture real-time colloidal crystal nucleation events. Moreover, as the thermodynamic driving force has remained undefined, data on key factors such as the critical nuclei size are at best semiquantitative13. Here we present real-time direct imaging and quantitative measurements of the pre- and post-nucleation processes of colloidal spheres, and the kinetics of nucleation driven by an alternating electric field, under well-defined thermodynamic driving forces. Our imaging approach could facilitate the observation of other rarely observed phenomena, such as defect and grain-boundary formation14 and the effects of foreign particles during crystallization15. Furthermore, it may prove useful in identifying optical and biological technologies based on colloids16,17,18,19,20,21.

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Figure 1: Method of assembling a 2D colloidal monolayer by controlling the alternating electric field (AEF).
Figure 2: Snapshots of the pre-nucleation process at multiples of t0 = 0.294 s, where t0 is the timing interval of the images.
Figure 3: Statistical measurements of parameters of nucleation kinetics.
Figure 4: Comparison of the colloidal assemblies obtained under constant electric field and under an AEF.


  1. 1

    Sato, K., Furukawa, Y. & Nakajima, K. (eds) Advances in Crystal Growth (Elsevier Science, Amsterdam, 2001)

  2. 2

    Abraham, F. F. Homogeneous Nucleation Theory (Academic, New York, 1974)

    Google Scholar 

  3. 3

    Kashchiev, D. Nucleation: Basic Theory with Applications (Butterworth-Heinemann, Oxford, 2000)

    Google Scholar 

  4. 4

    Laaksonen, A., Talanquer, V. & Oxtoby, D. W. Nucleation: Measurements, theory, and atmospheric applications. Annu. Rev. Phys. Chem. 46, 489–524 (1995)

    ADS  CAS  Article  Google Scholar 

  5. 5

    Chernov, A. A. Modern Crystallography III—Crystal Growth (Springer, Berlin, 1984)

    Google Scholar 

  6. 6

    Skripov, V. P. in Current Topics in Materials Science Vol. 2 (ed. Kaldis, E.) 328–378 (North-Holland, Amsterdam, 1981)

    Google Scholar 

  7. 7

    McGraw, R. & Laaksonen, A. Scaling properties of the critical nucleus in classical and molecular-based theories of vapor-liquid nucleation. Phys. Rev. Lett. 76, 2754–2757 (1996)

    ADS  CAS  Article  Google Scholar 

  8. 8

    Trau, M., Saville, D. A. & Aksay, I. A. Field-induced layering of colloidal crystals. Science 272, 706–709 (1996)

    ADS  CAS  Article  Google Scholar 

  9. 9

    Palberg, T. Crystallization kinetics of repulsive colloidal spheres. J. Phys. Condens. Matter 11, R323–R360 (1999)

    ADS  CAS  Article  Google Scholar 

  10. 10

    Larsen, A. E. & Grier, D. G. Like-charge attractions in metastable colloidal crystallites. Nature 385, 230–233 (1997)

    ADS  CAS  Article  Google Scholar 

  11. 11

    Yethiraj, A. & van Blaaderen, A. A colloidal model system with an interaction tunable from hard spheres to soft and dipolar. Nature 421, 513–517 (2003)

    ADS  CAS  Article  Google Scholar 

  12. 12

    Pusey, P. N. in Liquids, Freezing and the Glass Transition (eds Leveesque, D., Hansen, J. P. & Zinn-Justin, J.) Ch. 5 (Elsevier, Amsterdam, 1991)

    Google Scholar 

  13. 13

    Gasser, U., Weeks, E. R., Schofield, A., Pusey, P. N. & Weitz, D. A. Real-space imaging of nucleation and growth in colloidal crystallization. Science 292, 258–262 (2001)

    ADS  CAS  Article  Google Scholar 

  14. 14

    Lucadamo, G. & Medlin, D. L. Geometric origin of hexagonal close packing at a grain boundary in gold. Science 300, 1272–1275 (2003)

    ADS  CAS  Article  Google Scholar 

  15. 15

    Caccluto, A., Auer, S. & Frenkel, D. Onset of heterogeneous crystal nucleation in colloidal suspensions. Nature 428, 404–406 (2004)

    ADS  Article  Google Scholar 

  16. 16

    Lumsdon, S. O., Kaler, E. W., Williams, J. P. & Velev, O. D. Dielectrophoretic assembly of oriented and switchable two-dimensional photonic crystals. Appl. Phys. Lett. 82, 949–951 (2003)

    ADS  CAS  Article  Google Scholar 

  17. 17

    Norris, D. J. & Vlasov, Y. A. Chemical approaches to three-dimensional semiconductor photonic crystals. Adv. Mater. 13, 371–376 (2001)

    CAS  Article  Google Scholar 

  18. 18

    Kumacheva, E., Golding, R. K., Allard, M. & Sargent, E. H. Colloid crystal growth on mesoscopically patterned surfaces: effect of confinement. Adv. Mater. 14, 221–224 (2002)

    CAS  Article  Google Scholar 

  19. 19

    Pan, G. S., Kesmamoothy, R. & Asher, S. A. Optically nonlinear Bragg diffracting nanosecond optical switches. Phys. Rev. Lett. 78, 3860–3863 (1997)

    ADS  CAS  Article  Google Scholar 

  20. 20

    Khopade, A. J. & Caruso, F. Stepwise self-assembled poly(amidoamine) dendrimer and poly(styrenesulfonate) microcapsules as sustained delivery vehicles. Biomacromolecules 3, 1154–1162 (2002)

    CAS  Article  Google Scholar 

  21. 21

    Velev, O. D. & Kaler, E. W. In situ assembly of colloidal particles into miniaturized biosensors. Langmuir 15, 3693–3698 (1999)

    CAS  Article  Google Scholar 

  22. 22

    Fowler, R. & Giggenhein, E. A. Statistical Thermodynamics (Cambridge Univ. Press, London, 1960)

    Google Scholar 

  23. 23

    Yeh, S. R., Seul, M. & Shraiman, B. I. Assembly of ordered colloidal aggregates by electric-field-induced fluid flow. Nature 386, 57–59 (1997)

    ADS  CAS  Article  Google Scholar 

  24. 24

    Stiles, P. J. & Regan, H. M. Transient cellular convection in electrically polarized colloidal suspensions. J. Colloid Interface Sci. 202, 562–565 (1998)

    ADS  CAS  Article  Google Scholar 

  25. 25

    Trau, M., Sankaran, S., Saville, D. A. & Aksay, A. I. Electric-field-induced pattern formation in colloidal suspensions. Nature 374, 437–439 (1995)

    ADS  CAS  Article  Google Scholar 

  26. 26

    Crocker, J. C. & Grier, D. G. Methods of digital video microscopy for colloidal studies. J. Colloid Interface Sci. 179, 298–310 (1996)

    ADS  CAS  Article  Google Scholar 

  27. 27

    Liu, X. Y. in Advances in Crystal Growth Research (eds Sato, K., Nakajima, K. & Furukawa, Y.) 42–61 (Elsevier Science, Amsterdam, 2001)

    Google Scholar 

  28. 28

    Liu, X. Y., Maiwa, K. & Tsukamoto, K. Heterogeneous two-dimensional nucleation and growth kinetics. J. Chem. Phys. 106, 1870–1879 (1997)

    ADS  CAS  Article  Google Scholar 

  29. 29

    Auer, S. & Frenkel, D. Line tension controls wall-induced crystal nucleation in hard-sphere colloids. Phys. Rev. Lett. 91, 015703 (2003)

    ADS  CAS  Article  Google Scholar 

  30. 30

    Bowles, R. K. et al. A molecular based derivation of the nucleation theorem. J. Chem. Phys. 113, 4524–4532 (2000)

    ADS  CAS  Article  Google Scholar 

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We thank D.W. Li for help with the imaging process, and for discussions. We also thank C. Strom for reading the draft. This work was supported by the Science and Engineering Research Council of Singapore.

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Correspondence to Xiang Y. Liu.

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Competing interests

A provisional patent application (US application number, 60/519,573; filing date 12 November 2003) has been deposited for the technologically important development disclosed in this Letter, because it may have far-reaching industrial implications. Uncertain and indirect small-scale financial competing interests for the authors exist in the form of sharing in royalties provided, if the provisional patent application becomes regularized, and it results in licence agreements. Because the disclosed invention was done in the course of employment, the exclusive property might belong to the employer (NUS) who will be the assignee of a possible regular application.

Supplementary information

Supplementary Figure

Comparison of the critical size nc of nuclei from the experimental measurement, classical nucleation theory and nucleation theorem. (DOC 579 kb)

Supplementary Table

The measured kinetics parameters of nucleation of colloidal monolayer at the various values of the driving force. (DOC 70 kb)

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Zhang, KQ., Liu, X. In situ observation of colloidal monolayer nucleation driven by an alternating electric field. Nature 429, 739–743 (2004).

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