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.
Anmeldung
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