Electrochemical Properties and Measurements

Technical Workshop:

Electrochemical Properties and Measurements

Target Group: Researchers, engineers, and technical professionals

Group Size: min. 6, max. 16

Trainer: Harry Hoster, Ivan Radev

Scope: 3 h

Preliminary Outline:

Session 1: Thermodynamics and Electrochemical Potentials

• Conductivity of electrolytes, diffusion in electrolytes
• Basic principles of thermodynamics relevant to electrochemistry
• Gibbs free energy and its relationship with electrochemical potential
• Electrodes and electrode potentials. Potentionemtry. Definition and significance of standard electrode potentials
• Calculation of cell potentials using Nernst Equation
• Potential-pH (Pourbaix) Diagrams and electrode stability
• Introduction to reversible and irreversible processes
• Charge transfer kinetics, Butler-Volmer equation, Tafel equation
• Diffusion kinetics, Mass transport limiting effects, Galvanostatic potential-time curves. Diffusion in irreversible reactions

Learning Outcomes:

• Understand the fundamental thermodynamic principles behind electrochemical reactions.
• Be able to calculate and interpret electrode potentials under standard and non-standard conditions.

Session 2: Energy Values – HHV, LHV, and Thermoneutral Potentials
Topics Covered:

• Definitions of Higher Heating Value (HHV) and Lower Heating Value (LHV)
• Relevance of HHV and LHV in fuel cell and water electrolysis performance evaluation
• Thermoneutral potential: concept and calculation
• Relation between HHV, LHV, thermoneutral voltage and efficiency of electrochemical systems

Learning Outcomes:

• Distinguish between HHV and LHV and their implications for system efficiency.
• Calculate thermoneutral potentials and understand their relevance in heat management and safety.

Session 3: Electrochemical Kinetics – Rotating Disc Electrode (RDE) Techniques
Topics Covered:

• Principles of the Rotating Disc Electrode (RDE) method
• Hydrodynamics and mass transport in RDE
• Experimental setup and best practices
• Applications to key reactions:
  • Oxygen Reduction Reaction (ORR)
  • Hydrogen Oxidation Reaction (HOR)
  • Oxygen Evolution Reaction (OER)
  • Hydrogen Evolution Reaction (HER)
• Tafel analysis and kinetic parameter extraction, ECSA, kinetik current, mass and surface activity 

Learning Outcomes:

• Gain practical knowledge on using RDE for kinetic studies.
• Analyze and interpret RDE data for fundamental reactions in electrochemical energy systems.

Session 4: Electrochemically Active Surface Area (ECSA)
Topics Covered:

• Definition and importance of ECSA in catalyst evaluation
• Measurement techniques using cyclic voltammetry (CV)
• Hydrogen underpotential deposition (HUPD) and CO stripping
• Common artefacts and pitfalls:
  • Double-layer charging
  • Capacitive currents
  • Scan rate dependence
  • Effect of H2 partial pressure on HER, Hads and Hdes peaks

Learning Outcomes:

• Measure and interpret ECSA using CV techniques.
• Identify and mitigate artefacts in ECSA measurements.

Session 5: Polarization Curves and Performance Characterization
Topics Covered:

• Polarization curves: activation, ohmic, and concentration losses
• Experimental procedure and data acquisition
• IR compensation techniques
• Data analysis and performance benchmarking

Learning Outcomes:

• Conduct polarization curve measurements with precision.
• Analyze performance metrics and understand limiting factors in electrochemical devices.