Kinetics of electrode processes at solid-state interfaces
IR@CECRI: CSIR-Central Electrochemical Research Institute, Karaikudi
View Archive Info| Field | Value | |
| Title |
Kinetics of electrode processes at solid-state interfaces
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| Creator |
Gangadharaiyer, R.
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| Subject |
Electrodics and Electrocatalysis
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| Description |
In the first part of the thesis the concept of equilibrium potentials of the electrode, various
types of potential existing at various inter-phases are presented. Modern theories of the electrodes are
briefly reviewed.
The experimental part of the thesis describes the construction, performance, and accuracy of a
differential a.c. transformer bridge suitable for the Faradaic impedance measurements. The
experimental cell and details of the preparation of the reference electrodes are described. Faradaic
impedance measurements were made for the following systems
System Concentration with supporting electrolyte
1. Hg/Hg
2. Ag/Ag
2
2+
+
3. Ag/AgX/X
-
10
10
10
-6
-6
-6
N to 10
N to 10
N to 10
N XX
4. Ag/Agx/Ag
5. Ag/AgCl/Cl
+
-
10
10
-6
-6
N to 10
N to saturated XCl
6. Hg/Hg
2
X
2
/X
-
10
-6
N to 10
N Hg XX
7. Hg/Hg
8. Hg/Hg
2
2
X
2
Cl
/Hg
2
/Cl
2
2+
-
10
-6
N to 10
1 N to saturated XCl
9. Ag/AgX/X
-
, Glycerol 10
-6
N 10
N XX
10. Ag/AgX/Ag
+
, Glycerol 10
-6
-1
N to 10
-3
-3
-1
-1
-1
-2
-1
N Mg
2
N AgNO
N AgNO
N Hg
2
(
NO
3
3
(
NO
3
3
)
)
2
2
N
(
no supporting electrolyte
)
11. Hg/Hg
2
Cl
2
/Cl
-
1 N to saturated
(
no supporting electrolyte
)
12. Hg/Hg
2
Cl
2
/Cl
-
1 N to saturated
(
no supporting electrolyte
)
The results were analysed to obtain the exchange current of all systems. From the studies of the
variation of impedance with thickness of the film, it was possible to calculate the specific resistance and
hence the diffusion constant for the interstitial silver ions. From the gradient of the Randles plot and
knowledge of the diffusion constants, it was possible to obtain the concentration of interstitial silver
ions in the silver halides at room temperature. Both diffusion constant and concentration of interstitial
silver ions agree well with the values extrapolated from the high temperature data obtained by Wager
and Jost.
The equivalent circuit for the silver-silver halide electrode is proposed. It is shown that the two
important elements are a faradaic impedance at the silver-silver halide interphase in series with another
resistance associated with the building up of lattice, both being coupled.
The behaviour of mercury-mercurous halide electrodes has been also studied.
The optimum condition for good electrode performance is given with films of thickness prepared under
these optimum conditions, the diffusion have contained entirely within the solid state.
The thickness of the space charge within the solid phase has been calculated and the diffuse double
layer has been evaluated.
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| Date |
1969
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| Type |
Thesis
NonPeerReviewed |
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| Identifier |
Gangadharaiyer, R. (1969) Kinetics of electrode processes at solid-state interfaces. PhD thesis, Kerala University.
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| Relation |
http://cecri.csircentral.net/2818/
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