1st day. The bases of cyclic voltammetry

Class, 8:30 – 12:30 am (Cyrille Costentin)

  • Welcome to CVIS
  • Cyclic voltammetry of fast one-electron transfers (Nernstian responses)
  • Introduction to dimensionless formulations and to educated simulations
    • One-electron transfer to molecules immobilized on the electrode
    • One-electron transfer to free moving molecules
  • Technical aspects
    • The cyclic voltammetry experiment. Cell, electrodes and instrument
    • Faradaic and double layer charging currents
    • Ohmic drop. Resistance compensation
  • Successive one-electron transfers vs. two-electron transfers
  • Cyclic voltammetry of slow electron transfers
    • Immobilized and free moving reactants (investigating electron transfer kinetics by means of cyclic voltammetry)
    • Linear (Butler-Volmer) and non-linear (for outersphere, concerted dissociative and concerted proton coupled electron transfers) rate laws

Laboratory, 2:00 – 6:00 (or more) pm (Cyrille Costentin and Cédric Tard)

  • Cyclic voltammetry of a Nernstian system (e.g. anthracene in an aprotic solvent)
  • Ohmic drop and ohmic drop compensation with dummy and real cells
  • An example of slow electron transfer

2nd day. Coupled chemical reactions

Class, 8:30 – 12:30 am (Marc Robert)

  • The EC reaction scheme
    • Fast electron transfer, pure kinetic conditions
    • Governing equations, reaction profiles (reaction-diffusion layer)
    • Transitions from reversibility to irreversibility, determining standard potential and follow-up reaction rate constant
    • Zone diagram, travelling through the zone diagram
    • Competition between diffusion, chemical reaction and slow charge transfer
    • Concerted processes: competition between stepwise and concerted reactions, concerted proton-coupled electron transfers
  • Other case: dimerization

Laboratory, 2:00 – 6:00 (or more) pm (Marc Robert and Cédric Tard)1

  • Examples of EC mechanisms
    • 2-chloroanthracene in N,N’-dimethylformamide (EC first order, determination of standard potential and follow-up reaction rate constant)
    • Benzaldehyde (in ethanol at pH 12) (ECdim, determination of standard potential, electron transfer standard rate constant and dimerization rate constant)
  • Examples of concerted cleavages
    • Benzyl chloride (a concerted cleavage with a transfer coefficient close to 0.3)
    • Trichloroacetonitrile (a concerted cleavage with a sticky interaction between fragments)

3rd day. Catalytic systems

Class, 8:30 – 12:30 am (Cyrille Costentin)

  • Homogeneous systems
    • Principle: 1e-1 step reaction: zone diagram
    • Catalytic Tafel plots
    • Benchmarking of catalysts
    • Multi electron-multi steps catalytic reactions, case of 2e – 2 step reactions
  • Catalytic films
    • Monolayer coatings
    • Multilayer coatings

Laboratory, 2:00 – 6:00 (or more) pm (Cyrille Costentin and Cédric Tard)

  • Catalysis of electrochemical reduction of CO2 with Fe0tetraphenylporphyrin (Fe0TPP) as catalyst (in N,N’-dimethylformamide)
  • Investigation of different parameters influencing the catalytic response: scan rate, addition of acid
  • Analysis of the mechanism, catalytic Tafel plot

4th day. Redox enzymes

Class, 8:30 – 12:30 am (François Mavré)

  • Introduction to the cyclic voltammetry of redox enzymes
  • The ping-pong mechanism
  • Cyclic voltammetry of homogeneous redox mediated enzyme catalysis
  • Transposition to immobilized systems
  • How the Michaelis-Menten kinetics shows up in cyclic voltammetry
  • Illustrating examples of more complicated mechanisms
  • Mediated versus direct enzyme electrochemistry

Laboratory, 2:00 – 6:00 (or more) pm (François Mavré)

  • Cyclic voltammetric study of the redox mediated catalytic oxidation of glucose by glucose oxidase in homogeneous solution
  • Investigation of the different parameters influencing the catalytic response
  • Experimental approach of the redox mediated catalytic oxidation of glucose by a monolayer of glucose oxidase immobilized on an electrode surface

5th day. Questions from the floor

9:00 – 12:30 am

Cyrille Costentin, François Mavré, Marc Robert, Cédric Tard and Niklas von Wolff answer questions from the group.

  1. Half of the group will study 2-chloroanthracene and trichloracetonitrile, and the other half will study benzaldehyde and benzyl chloride. Interpretation and determination of parameters will be made by all students together.