Course Objectives: The learners should be able to apply theories in electrochemistry to analyze electrode kinetics.
Learning Outcomes: At the end of the course, the learners should be able to:
Write equations representing electrochemical cell, explain various overpotential involved during the operation of the cell.
Calculate electrochemical cell parameters, electrochemical active surface area, current and overpotential under given condition, amount of corrosion and its rate
Plot potential vs current, surface coverage vs. potential, potential vs. pH, concentration profile vs. distance from the electrode
Ionics: Electrochemistry of solutions, Ion-solvent interactions, ion-ion interactions, ionic migration and diffusion. Phenomenological description of transport processes. Thermodynamics of galvanic cells: Equilibrium electrode potentials, IUPAC convention for electrode potentials, Thermodynamics of electrochemical cells and applications.
Electrical Double layer: Theories of Double-Layer structure, diffuse-double-layer theory of Gouy and Chapman, the Stern Model, Adsorption of ions and neutral compounds, Electrocaplillary and differential capacitance measurements; Influence of double layer on charge transfer processes.
Reference electrodes: polarizable and non-polarizable systems. Types of reference and working electrodes
Electrode kinetics: Current-potential relationship (derivation of Butler-Volmer and Tafel equations). Adsorption isotherms for intermediates formed by charge transfer (Langmuir adsorption and its limitations, relating bulk concentration to surface coverage), Types of overpotentials: origin and minimization; mechanism of electro-organic reactions; hydrogen evolution and oxygen reduction reactions. transition state theory and Gibbs free energy of activation, bulk electrolysis; Quadratic activation –driving force relation –Marcus theory ; outer and inner sphere reactions. Underpotential deposition of metals and applications in catalysis.
Corrosion: Different types of corrosion; influence of environment; Evans diagram, Pourbaix diagram; corrosion rate measurements; Stern Geary equation; mixed potential theory and prevention of corrosion.