Cyclic Voltammetry for non-electrochemist

1. Cyclic Voltammetry –A Tutorial For
Non Electrochemist
Nakkiran Arulmozhi
PhD Candidate
Dr Jerkiewicz Lab

2. Black Box Method
Unknown
Input
Output
Effective scientific approach for testing unknown system
Choose the right input to get the required
Cyclic Voltammetry for Non Electrochemist CHEM-803 2

3. Electric Charge as Input
Unknown
Input
Output
Very sensitive and
selective
Elementary and
fundamental force
Convenient Input
Cyclic Voltammetry for Non Electrochemist CHEM-803 3
Inexpensive Easy control Space Requirement

4. Cyclic Voltammetry for Non Electrochemist CHEM-
803
Why Potentiostat is not in Every lab ?
4
Not a place and publish tool
A Thought Experiment to Show the Complexity

5. Thought Experiment
“ ”
Cyclic Voltammetry for Non Electrochemist CHEM-
803
Black Box
Pt wire
5

6. Black Box
Thought Experiment
Cyclic Voltammetry for Non Electrochemist CHEM-
803
“ ”
6

7. Thought Experiment
Black BoxH2SO4
Cyclic Voltammetry for Non Electrochemist CHEM-
803
7
Gas

8. Black Box
Multi-phase
Multi-Component
Decoding the Complexity
Cyclic Voltammetry for Non Electrochemist CHEM-
803
Multi-phenomena
8
Known Variable
Idealize the Unknown

9. How our group Uses CV
Cyclic Voltammetry for Non Electrochemist CHEM-
803
9
Surface Area
Surface Morphology
Reaction sites
Impurities
Adsorption properties
Catalytic properties
Corrosion properties

10. Cyclic Voltammetry - Theory
One-electron transfer process - Theory
Cyclic Voltammetry for Non Electrochemist CHEM-
803
X + e- Y
10
Completely reversible reaction
No Competing reaction
Electrode surface no effect on reaction kinetics

11. Cyclic Voltammetry
Scan Rate Voltage Range
Current
Cyclic Voltammetry for Non Electrochemist CHEM-
803
11
What factors that affect Output/Current in a the given system

12. Double Layer Charging
The expected response of a reversible redox couple
From A to B
----------
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
----------
Cyclic Voltammetry for Non Electrochemist CHEM-
803
12

13. Charge Transfer
At B
X
-Y
Cyclic Voltammetry for Non Electrochemist CHEM-
803
X + e- Y
13
The expected response of a reversible redox couple

14. Distance from Interface
Concentrationratio
Y
X
Distance from Interface
Concentrationratio
Y
X
X
Cyclic Voltammetry for Newbies
Concentration Profile

15. Mass transport
At C
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Y
X
X
X
X
X
Y
X
Y
X
X
Y
X
X
Y
X
Y
X
X
Y
Y
X
Y
x
Y
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
x
Cyclic Voltammetry for Non Electrochemist CHEM-
803
15
The expected response of a reversible redox couple

16. The Whole Picture
Distance from Interface
Concentrationratio
Y
X
Distance from Interface
Concentrationratio
Y
X
Distance from Interface
Concentrationratio
Y
X
Distance from Interface
Concentrationratio
Y
X
Distance from Interface
Concentrationratio
Y
X
Distance from Interface
Concentrationratio
Y
X
Cyclic Voltammetry for Newbies
Y X + e-

17. Application
redox potential for the analyte
Concentration
diffusion coefficient
number of electrons per molecule of analyte
Cyclic Voltammetry for Non Electrochemist CHEM-
803
17

18. Reference
Bard, Allen J.; Larry R. Faulkner (2000-12-18).
Electrochemical Methods: Fundamentals and
Applications (2 ed.). Wiley.
Kissinger, Peter; William R. Heineman (1996-01-23).
Laboratory Techniques in Electroanalytical
Chemistry, Second Edition, Revised and Expanded (2
ed.). CRC.
Zoski, Cynthia G. (2007-02-07). Handbook of
Electrochemistry. Elsevier Science
Cyclic Voltammetry for Non Electrochemist CHEM-
803
18

19. Acknowledgement
Dr Jerkiewicz and Lab members
Cyclic Voltammetry for Non Electrochemist CHEM-
803
19
Thanks for all your attention

20. Questions
Cyclic Voltammetry for Non Electrochemist CHEM-
803
20