Electrochemical Methods in Inorganic Chemistry

Examenvragen

4 september 2024

1. Planar diffusion (3 points)
   • Discuss the Cottrell equation for planar diffusion. What is planar diffusion and a planar electrode?
   • Which parameters can be determined experimentally from the Cottrell equation?
   • What does the concentration profile near the electrode of planar diffusion look like for:
     • fast kinetics
     • slow kinetics
   • Discuss the Cottrell equation for spherical diffusion at short and long times. What type of electrodes experience spherical diffusion?
2. Electrodepositions (2 points)
   • What happens at the initial stage of electrodeposition?
   • Which 3 modes can you distinguish in electrodposition?
   • How does the electrodeposition of a metal (or other) happen with chrono-amperometry? Demonstrate with a drawing!
   • How does the electrodeposition of a metal (or other) happen with cyclic voltammetry? Demonstrate with a drawing!
3. Kinetics (2,5 points)
   • Discuss the E-I-profile of a reaction with slow kinetics from 0 to infinite overpotential and give the relevant equation. When is a reactions kinetically controlled? What simplifications can be made in this region? What other regions are there and what are their names?
   • Define the kinetic parameters used in the E-I-profile and also explain how they can be calculated.
   • What are 3 possibilities of increasing the reaction rate. Explain your answers briefly.
4. Rotating Disk Electrode (2,5 points)
   • How is a RDE constructed? (only RDE is written in the question, not full name)
   • How does a RDE lead to a Levich plot,what conclusions can you pull from it and how does it prove reversility?
   • How do you use a Levich plot when the limiting current overlaps with the solvent limit?
   • What is an alternative to the Levich plot that can be used to calculate kinetic parameters?
5. Solitary questions (varying points)
   • What kinds of Chromium baths are there and how are they used? (1,5 points)
   • What Electrochemical Impedance Spectroscopy? How is it performed and what parameters can be determined from it and how? (1,5 points)
   • What is electrocatalysis? (1,5 points)
   • Explain crevice corrosion. How does it start, how does it evolve, what are the consequences and how can you prevent it? (2 points)
   • What is the Memory Effect in a rechargable battery? (1,5 points)
   • Discuss the lithium-sulphur battery. What are its mechanics on discharging, what are its properties, what are the advantages and disadvantages? (2 points)

15 januari 2024

1. UME-question (3 point)
   • Discuss the I-t plot of a UME
   • What does the concentration profile look like with fast and slow kinetics?
   • What are the start boundaries for the derivation of the Cotrell equation (without derivation itself).
   • What are the advantages and disadvantages of an UME?
   • What is the cell time constant, what are its components and what is its relation to r0?
2. Kinetics (3 points)
   • What is the E-I plot for slow kinetics from 0 to infinite overpotential? What are the different divisions and what is the boundary?
   • What are the starting points of a E-I derivation?
   • What does the concentration near the electrode look like for really low overpotential?
   • What are transfer coefficient, exchange current and overpotential? Give one method that can be used to determine each of these things.
3. Questions: explain briefly and write down the most important things:
   • Tin deposition (baths & properties) (2 points)
   • Pitting corrosion (2points)
   • Liquid junction potential and 1 example of ISE (1,5 points)
   • Square wave voltammetry. What are the advantages and disadvantages? How does it minimize potential drop, noise and charging current? (1,5 points)
   • Rotating disk electrode and the Levich plot. How can this method be used to calculate reversibility? (1,5 points)
   • What are solid-electrolyte-interfaces and why are they important? (1,5 points)
   • Give as many disadvantages of resistance in a cell (both laboratory and large scale cells) (2 points)
   • What is the C-rate of a battery? (1 point)
   • Forgot the last question (1 point)

16 januari 2023

1. Bespreking van volgende begrippen (2,5 punten per term):
   • Tin deposition (baths & properties)
   • Pitting corrosion
   • Liquid potential junction and 1 example of ISE
   • Square wave voltammetry
   • Rotating disk electrode
2. Beantwoord beide (4p per vraag)
   • UME, Cottrell
   • Kinetic control: Explain E-I plot and concentration behaviour for very low and moderately low overpotential (Butler-Volmer and Tafel plot etc.)

20 januari 2020 NM, verschillende reeksen

1. Bespreking van volgende begrippen (2,5 punten per term):
   • Evans diagram
   • Underpotential deposition
   • Electrocatalysis
   • Thin layer cell
   • Ionic liquids
2. Kies 1 van 2 vragen en bespreek uitvoerig (7,5 punten):
   • UME, Cottrell
   • Kinetic control: Explain E-I plot and concentration behaviour for very low and moderately low overpotential (Butler-Volmer and Tafel plot etc.)

14 januari 2019 VM, verschillende reeksen

1. Begrippen (2,5 punten per term):
   • Electrochemical cell as electronic circuit and impedance spectroscopy
   • Electrodeposition noble metals
   • Double layer
   • ISE based on pH-electrode (exNH3)
   • Intergranular corrosion
2. Kies 1 van de 2 vragen en bespreek uitvoerig (7,5 punten):
   • UME (working, how its made, pros and cons, effect on diffusion layer)
   • E-I plot. Describe plot. Give the relationship between the current and mox. What happens in steady state regim and what in non-steady state regim and how is the concentration near the electrode in both regims.

14 januari 2019 VM, verschillende reeksen

1. Bespreking van volgende begrippen (2,5 punten per term):
   • Methods to determine quality of SAM
   • The liquid potential junction and ISEs
   • How resistance effects cell time constant
   • Nickel Deposition
   • Crevice Corrosion
2. Kies 1 van 2 vragen en bespreek uitvoerig (7,5 punten):
   • The I-t plot for spherical diffusion, how concentration changes with time and start point of equation derivation.
   • Kinetic control. What does the Tafel plot mean? Explain the Buttler-Volmer equation, start of equation derivation.

Oral section - E-M read written answers and asked for brief explanation if a key term was missing.

1. Bespreking van volgende begrippen:
   • Tin deposition baths and their properties
   • Methods to determine the quality of SAM
   • Solid-based ion selective electrode for FET
   • Pitting corrosion
   • The rotating disc electrode
2. Kies 1 van de 2 vragen en bespreek uitvoerig
   • UME's
   • Kinetic control: Explain E-I plot and concentration behaviour for very low and moderately low overpotential (Butler-Volmer and Tafel plot etc.)

23 januari 2018 VM, verschillende reeksen

1. Bespreking van volgende begrippen:
   • ISE gebaseerd op hydrofobisch membraan
   • electrochemical impedance spectroscopy
   • transport number en transport in de bulk
   • initial stadia of electrodeposition on a foreign substrate
   • electrical double layer
2. Kies 1 van 2 vragen en bespreek uitvoerig:
   • crevice corrosion uitleggen,hoe het ontstaan en wat de gevolgen zijn
   • de I-t plot voor difussion controlled reaction met een planaire elektrode

1. Begrippen:
   • Electrodeposition baths Sn and properties
   • Electrotechnique to quantivy stabiliy sams
   • Solid based ion selective electrodes at ftr
   • Pitting corrosion
   • Rotating disk electrode
2. Kies 1 van 2 vragen en bespreek uitvoerig:
   • CvmV of i-t met Ume

15 januari 2018 VM, verschillende reeksen

1. Bespreking van volgende termen
   • Electroplating baths van Ni deposities
   • Pitting corrosion
   • Rotating Disk Electrode
   • Ion selective electrode bij FETs
   • Electrochemische methode om stabiliteit van SAMs te quantificeren
2. Kies 1 van 2 vragen en bespreek uitvoerig
   • Wat is cyclic voltammetry. Leg procedure uit van meting. Wat is de beperking van deze techniek? Wat verandert er met de scan rate etc.
   • UMEs: hemispherical diffusion. Wat is het startpunt voor de afleiding etc.

1. Bespreking van volgende termen:
   • square wave voltammetry
   • mass transport controlled reactions
   • copper deposition in chips
   • double layer en charging current
   • crevice corrosion
2. Kies 1 van 2 vragen en bespreek uitvoerig:
   • UME's uitleggen
   • I-t plot spherical diffusion. startpunt van afleiding uitleggen, hoe evolueert diffusielaag over tijd

1. Bespreking van volgende termen:
   • Damascene proces
   • Electrocatalysis
   • Transport number en transport in bulk
   • soorten ISE's
   • duck-shaped curve in reversibele processen
2. Kies 1 van 2 vragen en bespreek uitvoerig:
   • I-t plot bij sferische diffusie
   • Butler volmer en tafel plot bij kinetische controle

20 januari 2017 VM, verschillende reeksen

1. Bespreking van volgende termen
   • Liquid junction ISE with hydrophobic membrane
   • Electrochemical Impedance Spectroscopy
   • the initial step for electrodeposition
   • Current through bulk and transport number ti
   • Electrical double layer
2. Kies 1 van 2 vragen en bespreek uitvoerig
   • I-t plot for planar diffusion. What is the behaviour of the concentration near the electrode over time? What is the starting point for the Cottrell equation?
   • Crevice corrosion volledig uitleggen

1. Bespreking van volgende termen
   • UME, geef voor- en nadelen
   • Chrono-amperometrie
   • Nernst-Planck vergelijking. Waardoor wordt het transport in de bulk gekenmerkt?
   • Evans diagram uitleggen
   • tertiaire current distribution
2. Kies 1 van 2 vragen en bespreek uitvoerig
   • I-t plot for spherical diffusion. What is the behaviour of the concentration near the electrode? What is the starting point for the Cottrell equation?
   • Bespreek de tafel-plot

15 januari 2014 VM

1. Bespreking van volgende termen
   • Damascene process and influence of additives
   • Tafel plot
   • Types of ion selective electrodes
   • Electrocatalysis
2. Kies 1 van 2 vragen en bespreek uitvoerig
   • E-I plot for spherical diffusion
   • Cyclic Voltammetry

14 januari 2013 NM, verschillende reeksen

1. Enkele termen kort bespreken (2,5 punten per term)
   • Explain what happens when the energy barrier is shifted. Explain α?
   • Nernst-Planck and explain the transport of current in the bulk.
   • Cell time constant
   • tertiary current density
   • chrono-amperometry of an electrodeposition
2. Twee vragen waaruit je er een moet kiezen om uitgebreid te bespreken (7,5 punten)
   • What does the Tafel plot mean? Explain the Buttler-Volmer equation. Where does it come from? (en nog wat dingen)
   • Explain the E-I plot following a potential step under diffusion control for a spherical electrode. What is the behaviour of the concentration near the electrode over time? What is the starting point for the Cottrell equation? Give the current vs time equation and where does it come from?

1. Enkele termen kort bespreken (2,5 punten per term)
   • Electrodeposition from ionic liquids
   • Thin layer cell
   • Current decay profile from the relationship of Shoup and Szabo
   • Electrocatalytic reactions
   • Underpotential deposition
2. Twee vragen waaruit je er een moet kiezen om uitgebreid te bespreken (7,5 punten)
   • Kinetic control. What does the Tafel plot mean? Explain the Buttler-Volmer equation. Where does it come from?
   • Mass diffusion control. Explain the E-I plot following a potential step under diffusion control for a planar electrode. What is the behaviour of the concentration near the electrode over time? What is the starting point for the Cottrell equation?

1. Enkele termen kort bespreken (2,5 punten per term)
   • Liquid junction ISE with hydrophobic membrane
   • Electrochemical Impedance Spectroscopy
   • Additive effect
   • Current through bulk and transport number
   • Electrical double layer
2. Twee vragen waaruit je er een moet kiezen om uitgebreid te bespreken (7,5 punten)
   • Waardoor is het begin van een elektrodepositie gekenmerkt? Bespreek de verschillende modes van dit initiële proces. Hoe wordt elektrodepositie herkend in een CV.
   • Bespreek chrono-amperometrisch plot voor een potential step voor een elektrodepositie/nucleatieproces.