The Influence of Thin Gold Electrodes on the High-Temperature Impedance of Oxide Glasses
Round 1
Reviewer 1 Report
Good paper though not easy to understand exactly what the results show, good to publish this stage to help build on this for the future (you or other groups).
Minor spelling comments:
line 14 insert "the" before gold
line 112 remove "the" before color
line 115 "process corelated with electrodes" - vague! could you expand please?
line 131 reproducible not repetitive
line 169 section not chapter
Otherwise nice paper.
Author Response
Response to reviewer 1
Manuscript ID: coatings-1752479: The Influence of Thin Gold Electrodes on the High-Temperature Impedance of Oxide Glasses.
Explanations and answers to the comments of the reviewer 1 are given below. Corresponding changes, corrections or re-phrasings are marked using the "Track Changes" function in Microsoft Word.
Reviewer 1: Good paper though not easy to understand exactly what the results show, good to publish this stage to help build on this for the future (you or other groups).
Comment 1#: Minor spelling comments:
line 14 insert "the" before gold
line 112 remove "the" before color
line 131 reproducible not repetitive
line 169 section not chapter
We are thankful to the reviewer for the appreciation of our research work and for valuable comments. We have changed all listed language mistakes.
Comment 2#: line 115 "process corelated with electrodes" - vague! could you expand please?
This low frequency process may be related with the processes at the glass/gold electrode interface: formation of ionic double layers and an interfacial charge transfer which are called electrode effects. We added one more sentence to explain the electrode effects which are typically observed in ionic conductors (see line 105).
Author Response File: 
Author Response.doc
Reviewer 2 Report
The manuscript is interesting and it needs revision due to following issues.
1. The English is to be improved further. 2. The resolution of figures is to be increased. 3. The methods of conductivity measurement are to be discussed. 4. Introduction should be revised with some more references. 5. The formula for measuring conductivity and discussion is needed. See some references.
https://doi.org/10.1016/j.materresbull.2021.111618
https://doi.org/10.1016/j.ceramint.2019.11.042
https://doi.org/10.1016/j.cjph.2022.02.001
https://doi.org/10.1016/j.matchemphys.2021.125598
https://doi.org/10.1016/j.jmat.2015.09.003
https://doi.org/10.1016/j.matchemphys.2020.123902
6. Cole-Cole plots are to be discussed further.
https://doi.org/10.1016/j.cplett.2020.137552
https://doi.org/10.1016/j.jnoncrysol.2021.120721
Author Response
Response to reviewer 2
Manuscript ID: coatings-1752479: The Influence of Thin Gold Electrodes on the High-Temperature Impedance of Oxide Glasses.
Explanations and answers to the comments of the reviewer 1 are given below. Corresponding changes, corrections or re-phrasings are marked using the "Track Changes" function in Microsoft Word.
Reviewer 2: The manuscript is interesting and it needs revision due to following issues.
Comment 1#: The English is to be improved further.
We tried to improve the English language and we also used a special program to do it.
Comment 2#: The resolution of figures is to be increased.
We increased the resolution of all figures as well as the size of symbols and text.
Comment 3#: The methods of conductivity measurement are to be discussed.
We have added a detailed description of conductivity measurements in the Materials and Methods part.
Comment 4#: Introduction should be revised with some more references.
We revised the Introduction by including the appropriate suggested references.
Comment 5& 6#: The formula for measuring conductivity and discussion is needed. Cole-Cole plots are to be discussed further. See some references.
https://doi.org/10.1016/j.materresbull.2021.111618
https://doi.org/10.1016/j.ceramint.2019.11.042
https://doi.org/10.1016/j.cjph.2022.02.001
https://doi.org/10.1016/j.matchemphys.2021.125598
https://doi.org/10.1016/j.jmat.2015.09.003
https://doi.org/10.1016/j.matchemphys.2020.123902
https://doi.org/10.1016/j.cplett.2020.137552
https://doi.org/10.1016/j.jnoncrysol.2021.120721
https://doi.org/10.1016/j.jallcom.2021.159216
We have added more information about the conductivity measurements and Nyquist plots analysis discussion.
Author Response File: Author Response.doc
Reviewer 3 Report
In this work, the authors mainly investigated the influence of thin gold electrodes on the electrical measurements of oxide glasses at high temperatures by impedance spectroscopy. The results showed the electrical performance can deteriorate at a temperature around 600 K during heating due to the possible thermal disintegration of gold layer on glasses. And the authors recommended that several factors should be taken into account in the preparation of sample for electrical measurements, including the thickness of gold electrode, the heating, cooling or both in the high temperature measurements. To sum up, this work is interesting and useful. Revision is suggested before publication:
(1) The author mentioned that “frequency-dependent conductivity part visible at frequencies lower than 1 Hz and temperatures above 413 K, which can be correlated with electrode effects and is often observed for ionic conductors” in line 103. What does the electrode effect refer to in the sentence?
(2) How did the authors conduct the third measurement in line 116? Was it after the second measurement? If so, how is the experimental temperature consistent with the first measurement by means of cooling? It is strongly recommended that the authors describe the experimental process in more detail, so that readers can better understand the conclusions reached by the authors.
(3) All pictures in this paper are not clear, the resolutions should be improved.
(4) The equivalent circuit should be provided in the Nyquist diagram. In addition, why only data at 383 K are selected for impedance analysis? The anomalous changes in resistivity begins around a temperature of 603 K. Why there is no impedance analysis at this temperature presented as a reference?
(5) How is the activation energy calculated in line 216? Please explain it simply. According to the Arrhenius law, the calculation of activation energy is related to the selected temperature range. Is the big discrepancy of activation energy mentioned by the authors related to the selected temperature range? In addition, what is the frequency boundary between low-frequency and high-frequency regions in line 219?
Author Response
Response to reviewer 3
Manuscript ID: coatings-1752479: The Influence of Thin Gold Electrodes on the High-Temperature Impedance of Oxide Glasses.
Explanations and answers to the comments of the reviewer 1 are given below. Corresponding changes, corrections or re-phrasings are marked using the "Track Changes" function in Microsoft Word.
Reviewer 3: In this work, the authors mainly investigated the influence of thin gold electrodes on the electrical measurements of oxide glasses at high temperatures by impedance spectroscopy. The results showed the electrical performance can deteriorate at a temperature around 600 K during heating due to the possible thermal disintegration of gold layer on glasses. And the authors recommended that several factors should be taken into account in the preparation of sample for electrical measurements, including the thickness of gold electrode, the heating, cooling or both in the high temperature measurements. To sum up, this work is interesting and useful. Revision is suggested before publication:
Comment 1#: The author mentioned that “frequency-dependent conductivity part visible at frequencies lower than 1 Hz and temperatures above 413 K, which can be correlated with electrode effects and is often observed for ionic conductors” in line 103. What does the electrode effect refer to in the sentence?
In ionic conductors, the current can be limited by ionic double layer formation most likely at the glass/gold electrode interface. The formation of ionic double layers and an interfacial charge transfer are referred as electrode effects. We added the explanation in the text (in line 122).
Comment 2#: How did the authors conduct the third measurement in line 116? Was it after the second measurement? If so, how is the experimental temperature consistent with the first measurement by means of cooling? It is strongly recommended that the authors describe the experimental process in more detail, so that readers can better understand the conclusions reached by the authors.
We added more details to the description of the experimental part to clarify the order and conditions of conducted measurements (see lines 75-88).
Comment 3#: All pictures in this paper are not clear, the resolutions should be improved.
We increased the resolution of all figures as well as the size of symbols and text.
Comment 4#: The equivalent circuit should be provided in the Nyquist diagram. In addition, why only data at 383 K are selected for impedance analysis? The anomalous changes in resistivity begins around a temperature of 603 K. Why there is no impedance analysis at this temperature presented as a reference?
The impedance analysis was done in the full possible temperature range. The obtained conductances in fig. 4 are the result of fitting the Nyquist plots in the other temperatures the fitting of the equivalent circuit was incorrect. The presented plots in fig. 3 are the only examples that should show the relaxation processes and fitting results. The temperature 383 K was selected because it overlapped for both low- and high-temperature measurements. The highest possible temperature at which the fitting was possible and gives reasonable results was 473 K. Above, the nonlinearity correlated with the electrode effects (like double-layer formation) is not negligible and the correct estimation of two relaxation processes was impossible. We added the explanation in the text and the equivalent circuit in the Nyquist diagram (see fig. 3a and 3c).
Comment 5#: How is the activation energy calculated in line 216? Please explain it simply. According to the Arrhenius law, the calculation of activation energy is related to the selected temperature range. Is the big discrepancy of activation energy mentioned by the authors related to the selected temperature range? In addition, what is the frequency boundary between low-frequency and high-frequency regions in line 219?
The activation energy is calculated based on the linear fitting of conductance values multiplied by the temperature and presented as a function of reciprocal temperature ln(σT) = f(T-1). This dependence showed linear behavior in a wide temperature range which is typical for ionic conduction. The linear fitting showed good agreement with the experimental data. In the paper, we have shown the conductance as a function of 1000T-1 as is customary to facilitate the analysis of conductivity values. We have added this explanation in the text (lines 255 - 260). The temperature ranges for which the activation energy was calculated are different between LT and HT measurements as can be visible in Fig. 4. However, between measurements conducted in high temperatures, the temperature regions selected for activation energy estimations are similar while the highest discrepancy was found between 2nd m HT and 7th m HT therefore we believe that it is not a reason. As can be seen in Nyquist plots (fig. 3) two relaxation processes highly overlapped in most of the cases therefore it is hard to define the boundary frequency that separates the low- and high-frequency regions. However, the obtained relaxation times are 100 up to 1000 times different between high- and low-frequency relaxation processes.
Author Response File: Author Response.doc
Round 2
Reviewer 2 Report
Now the revised version of the manuscript can be accepted for publication.
