Physical Chemistry of Surfaces

Recommended Prerequisites

General Chemistry, Chemical Thermodynamics.

Teaching Methods

There are theoretical (T) and theoretical-practical (TP) lectures. In the first, theoretical concepts are presented followed by their applications through the presentation of case studies that are discussed and solved in class. Students are encouraged to solve exercises in TP class, where discussions with their colleagues are allowed. Some problems are also proposed for autonomous solving which are then discussed in following TP class. There will be also experimental demonstrations of available characterization techniques.

Learning Outcomes

General Objectives:

Acquisition of knowledhe about Physical/Chemistry phenomena occuring at interfaces (between solids, gases and liquids).

Specific objectives:

a) to know how to estimate the transport properties of pure fluids and mixtures;

b) to know how to apply the concept of surface energy to study capillary phenomena; ahesion and cohesion; wetting;

c) to understand and characterize physical adsorption at interfaces solid/gas and solid/liquid; analyse the mechanisms for chemical adsorption and its application in heterogeneous catalysis;

d) identify and characterize colloidal systems; understand the factors that determine the stability of a colloidal dispersion; correlate molecular interactions with macroscopic behaviour leading to coagulation or flocculation.

Develop competencies to understand the behaviour of different products and materials of everyday usage involving inerfacial phenomena.

Work Placement(s)

No

Syllabus

1. Estimation of transport properties in gas, gaseous mixtures, liquids and liquid mixtures;

2. Surface free energy. Lennard-Jones diagram. Surface tension and contact angle. Laplace and Kelvin equations. Young-Laplace equation. Cappilarity: Adhesion and cohesion. Wetting. Surface tension measurement.

3. Adsorption of gases in solids. Gibbs equation. Chemical adsorption:  Langmuir - Blodgett films. 2-D Isotherms. Physical adsorption: Langmuir-Hinshelwood mechanism.

4. Electric-double layer. Schulze-Hardy rule. Coagulation and flocculation. Surfactants and flocculants. Description and selection of syrfactants. Stabilization of interfaces. Colloids: stabilization and kinetics of de-stabilization. Stabilization parameter. Critical coagulation concentration (ccc).

Head Lecturer(s)

Maria da Graça Bontempo Vaz Rasteiro

Assessment Methods

Assessment
Synthesis work: 30.0%
Exam: 70.0%

Bibliography

- But, Hans-Jurgen;  Kappl, M. Surface and Interfacial Forces. 1th ed, Wiley-VCH, Darmstadt, 2010

- Morrison, I.D.;  Ross, S. Colloidal Dispersions-Suspensions, Emulsions and Foams. 1th ed, Willey., New York, 2002

- Myers, D. Surfaces, Interfaces, and Colloids – Principles and Applications. 2dn ed, Wiley, New York, 1999

- Adamson, A. W. Physical Chemistry of Surfaces. 6th ed, Wiley, New York, 1997

- Stokes, R.J., Evans, D.F., Fundamentals of Interfacial Engineering.  Advances in Interfacial Engineering Series, Wiley,  New York, 1996

- Hiemenz, P.C.  Colloid and Surface Chemistry. Marcel Dekker, New York, 1986

- Gregg, S.J.; Sing, K.S.W. Adsorption Surface Area and Porosity. 1th ed, Academic Press Inc., London, 1969