Colloid and Interface Science

Colloids are formed by particles, bubbles or droplets with a size d that is typically in the range of tens of nanometer to microns, dispersed in a continuous phase formed by molecules much smaller than d. We constantly encounter colloids in our natural surroundings, for instance in foods, in marine life or in our bodies, as well as in numerous industrial products, from cosmetics to paints. The field of colloid and interface science is sometimes referred to as “the bridge to nanoscience”. It plays a vital role in efficient processing and handling of nanoparticles and many self-assembled nanoscale systems are colloidal in nature. Since nano- and microparticles are characterized by small size and large surface-to-volume ratio, the interface with the surrounding becomes extremely important. Knowledge of interface science is thus key to understanding, preparing, handling and applying these systems, but it is also at the core of fascinating phenomena observed on larger scale, ranging from capillary forces to atomically smooth surfaces to superhydrophobicity. The course will bring a fundamental understanding of colloid and interface science that is then applied to the modern research fields of nano science and technology.

Main course book
Applied Colloid and Surface Chemistry (Wiley)
Richard M. Pashley and Marilyn Karaman
Secondary course book
An Introduction to Interfaces and Colloids: The Bridge to Nanoscience (World Scientific) John C. Berg
Further useful books
Fall semester 2012
The class starts on Thursday September 6th 2012 at 9:30 am in room 83-503 (Gwanak campus). The following lectures will be as follows:
  • Even course weeks (13.09 etc.): D-111 (Gwanggyo campus).
  • Odd course weeks (20.09 etc.): 83.201 (Gwanak campus).
PDFs of the slides shown during the lectures will be available for download from the course resources page once the course has started.Schedule (week by week):
  1. Introduction to colloid and interface science & its applications. Basic concepts. Van der Waals interactions, hydrogen bonding and the hydrophobic effect.
  2. Surface and interfacial tension. Surfactants/amphiphiles and their applications. Practical colloid preparation methods.
  3. Stability of colloids: Brownian motion vs. gravity and viscosity. Introduction to steric vs. electrostatic colloid stabilization.
  4. Destabilization of colloids: aggregation, flocculation, sedimentation and centrifugation. Depletion attraction. Characterization of colloids: scattering, microscopy, rheology.
  5. Lab exercise 1: Preparation of colloids via dispersion and condensation and their characterization. (2 consecutive lecture hours Tuesday or Wednesday)
  6. The electric double layer. The Poisson-Boltzmann equation, the Debye length and the zeta potential.
  7. The Hamaker approach to describing van der Waals attraction. DLVO theory of colloidal stability.
  8. Wetting and dewetting. Contact angle and contact angle hysteresis. Laplace pressure and the Young-Laplace equation. Introduction to capillary phenomena.
  9. Mid-term exam. Capillary condensation and the Kelvin equation.
  10. Wenzel and Cassie-Baxter models for hydrophilic and hydrophobic surfaces. Practical approaches to superhydrophobic/superhydrophilic surfaces.
  11. Emulsions, foams and gels and their respective applications. Ostwald ripening. Percolation.
  12. Lab exercise 2: Preparation of emulsions and foams and their characterization. (2 consecutive lecture hours Tuesday or Wednesday)
  13. Thermodynamics of adsorption; Gibbs adsorption equation. Surface area determination by gas adsorption experiments (Langmuir and BET isotherms).
  14. Course review, example problem solving, additional topics of interest
  15. Final exam; 2 consecutive lecture hours written exam or individual 60 minute slots oral exam.
Consultation Place/Time (English) : office D-309 (Gwanggyo campus, GSCST), Wednesdays 10-12 during the course period.

Welcome !

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