Thickness and Humidity on Proton Conductivity in MOF-508 Thin Film by Twin-Zinc-Source Method
Round 1
Reviewer 1 Report (New Reviewer)
In this paper (coatings-2558912), the authors investigated the thickness and humidity on proton conductivity by twin zinc source method. The topic is interesting for the target readers and the results are acceptable. But there are some problems in the writing, presentation, and discussion of the results.
1. Title: It is recommended to include specific materials in the title. The first letter of all words in the title is uppercase.
2. Abstract and results: “water sensitive detector” is not accurate. The relative humidity used in the experiment. So it should be expressed as “ humidity sensor” or “for humidity detection”.
3. “The relative humidity was controlled by sealing the MOF-508a microfilm in a quartz cell that contained salt solutions at various saturations at room temperature…” The specific saturated salt solutions and corresponding relative humidity (RH) values need to be given.
4. Figure 3: The length of the scale needs to be marked or explained in figure captions.
5. “potential of water sensitive detector [40]”. Reference 40 is baseless and it is recommended to cite literature on humidity sensors. In addition, it should be expressed as “humidity sensor” or “for humidity detection”.
6. The inset in Figure 7 is not clear, it is recommended to increase the font size and line width.
7. Figure S5 seems to have not been cited or discussed.
8. The analysis in Figure 9 is too rough, and it is recommended to discuss it in conjunction with literature and humidity sensor characteristics, and refer to Sensors Actuators, B Chem. 317 (2020) 128204.
9. The information in reference 28 is incomplete and can be replaced by the latest literature on humidity sensors.
10. Check the format of the references. The format is incorrect, the information is incomplete, the journal name is not properly abbreviated, and the numbers in the chemical formula require subscripts. “[]” does not require superscribing.
11. Check the format. Figure instead of figure, Figure S instead of Figure s. Check for similar errors.
12. English needs polishing.
English needs polishing.
Author Response
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Author Response.pdf
Reviewer 2 Report (Previous Reviewer 3)
The authors have synthesized MOF thin film on Zn substrate as a stable structure and high proton conductive materials. In the new version some of concerns has been addressed, although there some issue which should be explained.
1. The authors should provide the highlights of their work and the novelty regarding other papers.
2. The author claimed that the thickness has been changed linealy with the Zn concentration. They have used SEM to prove this. The SEM micrograph is not a validate result to claim on thickness, as the micrograph is on a small area and also the thckness which is calculated is not accurate enough.
3. The authors mentioned that "and yet more surprisingly, the material’s resistivity also changed with the thickness of the film", How have you calculated the resistivity?! If you used the EIS and resistivity from that why the resistivity should be constant?!
4. The corresponding phase marked with asterisk symbol in Fig. 5 should be presented in the Figure.
5. The results should be compared with others researches.
6. The English editing was useful and the grammatical errors are addresse. Although, some parts of paper still needs a revision for being apprehensible. For instance this sentence is grammatically right but can be write better to be more apprehensible: "This was followed by reflux condensation at 90 °C in an oil bath for 24 h, 83 then removing it after cooling, cleaning it with DMF and n-hexane, respectively, 3 times 84 each, and then drying it in the air. Then removed the guest molecule, placed the samples 85 in a vacuum drying oven at 120 °C for 24 hours."
The English editing was useful and the grammatical errors are addresse. Although, some parts of paper still needs a revision for being apprehensible.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report (Previous Reviewer 2)
The manuscript entitled "Thickness and Humidity Effects on Proton Conductivity Using the Twin Zinc Source Method" presents a captivating and highly valuable research topic. The study systematically examines the proton conductivity and water/moisture adsorption behavior of MOF-508b/Zn. The anhydrous conductivity results are particularly intriguing, and the conductivity exhibited an increase at higher humidity levels, which can be attributed to a promising hopping mechanism. The findings showcased in this manuscript contribute significantly to the field, although the proton conductivity values remain inferior compared to most MOF materials. To further strengthen the manuscript, the authors should provide more compelling stability studies and elaborate on the material's structural and stability aspects.
Based on a careful review, I recommend accepting this manuscript upon addressing the following minor points:
1. Authors should present the post-proton conductivity samples' PXRD (Powder X-ray diffraction) data under varying humidity levels and higher temperatures. This will aid in understanding the material's structural changes and its implications on proton conductivity.
2. Additionally, the authors should include N2 sorption isotherms for both as-made and pristine MOF-508b/Zn materials. Referencing the works of Evans et al. (J. Am. Chem. Soc. 2023, 145, 17, 9850–9856), and other relevant sources (Sci. Adv. 8, eade1473 (2022) and ACS Omega 2022, 7, 18, 15275–15295; ACS Applied Nano Materials 2 (8), 5169-5178)) will help establish material purity and reproducibility.
3. It is recommended that the authors perform recyclability tests to assess the material's reusability and stability over multiple cycles. This information will be valuable in practical applications.
4. A detailed description of the MOF-508b/Zn thin film preparation, along with its structural and stability studies, should be provided. This will enhance the reproducibility and applicability of the results.
5. To place the study in context, the authors should present literature comparison tables for state-of-the-art MOFs and thin-film materials, providing readers with a comprehensive understanding of the research's significance and progress in the field.
Author Response
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Author Response File: Author Response.pdf
Reviewer 4 Report (New Reviewer)
Please find the detailed review comments in the attached file.
Comments for author File: Comments.pdf
Minor English editing is required especially in the results and discussion section of the manuscript.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report (New Reviewer)
The response and revised manuscript are satisfactory and recommended for publication.
In the proof stage, it is necessary to check the format of the references, such as the completeness of the references information (year, volume number, page number/literature number), subscripts for chemical formula numbers, and abbreviations for journal names.
Reviewer 2 Report (Previous Reviewer 3)
The authors have addressed all the concerns and the paper can be accepted in the Coatings journal in present format.
Minor editing of English language required
Reviewer 4 Report (New Reviewer)
The authors have addressed all the review comments. Moreover, the figures and graphs in the revised manuscript are upto the acceptable quality. Thus, the present form of the revised manuscript may be accepted for publication
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
The problem that has been studied is interesting and will attract the attention of those working in this field. For these reasons, I recommend the acceptance of this paper in the Journal.
However, before that, the Editor makes a decision, I suggest that the authors must take into account the corrections proposed in the below section "Comments for Author".
1. The specific applications of the structure under consideration " twin zinc 2 source method " has not been explained well.
2. The source of basic equations must be written.
3. It could be very interesting if authors can provide real materials with assumed material properties. How these material parameters were obtained? Otherwise, the problem looks like a mathematical exercise.
4. What is the main objective behind the current study? It is beneficial for the readers to add more explanations about the novel contribution of this method from theoretical/experimental viewpoints.
5. - The authors must explicitly declare the assumptions and limitations of their model. It seems its application is quite restricted while computational methods are capable of dealing with a much wider application range.
6. - The introduction part needs to be extended by discussing more relevant papers. The authors should appropriately extend this section by discussing more relevant works focusing on different methods and models in the literature. Specifically, the authors should carefully discuss previous papers.
7. - It is suggested to add a more in-depth explanation of the model, its justification, and more discussions on the results.
8. - Is the presented method capable of solving the nonlinear behavior of the system? Please explain the procedure if any.
9. - The paper should be carefully double-checked from a grammatical point of view.
10. The results presented in this study were not verified and no one can check the integrity of the mathematical modeling.
11. The obtained findings of this work should be compared to experimental results or at least with other published results in the literature.,
12. The authors should try to give advantages of using their method compared to others.
13. The authors need to explain that the numerical approach used in the research is one of the appropriate solutions in the context of the research problem. What are the achievements of previous studies based on a numerical basis? Also, describe what has not been achieved.
Minor editing of English language required
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
The manuscript titled "Thickness and humidity on proton conductivity by twin zinc source method" discusses an important topic in the field of fuel cells: proton conductivity. The authors synthesized MOF-508a thin films using the atmospheric "twin-zinc-source" method. They then performed SEM, XRD, and TGA characterizations of the films and studied their proton conductivity activity under various dry and humid conditions. The electrochemical studies provided in the manuscript are interesting but not significant in the research. Authors shod provide a thorough electrochemical characterization and analytical studies of Materials. However, before submitting this manuscript, the authors should address the following points:
1. They should include an Arrhenius plot in the manuscript.
2. They should conduct gas sorption and BET analysis of the MOF thin films. This would provide more information about the surface area and porosity of the films, which could affect their proton conductivity.
3. They should provide water sorption isotherms. This would show how the films absorb water vapor as a function of humidity, which could also affect their proton conductivity.
4. In the PXRD data, the authors should present all of the full signals, not just the peaks. This would allow readers to understand the crystal structure of the films better.
5. The manuscript requires English editing. There are many grammatical errors and typos, which makes it difficult to read.
6. They should provide the proposed mechanism for proton conductivity and must include the MOF structure.
The manuscript requires English editing. There are many grammatical errors and typos, which makes it difficult to read.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
The authors have synthesized MOF thin film on Zn substrate as a stable structure and high proton conductive materials. In this study, the author should highlight the novelty and highlights of their work. More reasoning and discussions are needed and therefore the paper needs a major revision. Some of the issues which should be addressed are as follow:
1. The authors should provide the highlights of their work and the novelty regarding other papers.
2. The manuscript need a whole revision on the English language. Some parts of the text is incomprehensive such as : line 71: "The remove the guest molecule, placed the samples in 71 a vacuum drying oven at 120 °C for 24 hours."
3. The subtitle of section 2 should be revised. For example: "XRD, SEM, TGA" is not a subtitle. It is suggested that tou have two subtitle, one for materials preparation and the other one for characterizations.
4. The author claimed that the thickness has been changed linealy with the Zn concentration. They have used SEM to prove this. The SEM micrograph is not a validate result to claim on thickness, as the micrograph is on a small area and also the thckness which is calculated is not accurate enough.
5. The authors mentioned that "and yet more surprisingly, the material’s resistivity also changed with the thickness of the film", How have you calculated the resistivity?! If you used the EIS and resistivity from that why the resistivity should be constant?!
6. Figure 1, in the XRD some peaks are missing.
7. The EC of the EIS data should be presented and the corresponding data should be discussed. I believe the paper can be improved by more discussion about the results. In this version, the paper is in technical report format rather than scientific paper.
8. The corresponding phase marked with asterisk symbol in Fig. 8 should be presented in the Figure.
9. The conclusion should be revised with some discussion and reasoning for the results
10. The results should be compared with others and more paper should be revised in the introduction part to cover other researches.
The manuscript need a whole revision on the English language. Some parts of the text is incomprehensive such as : line 71: "The remove the guest molecule, placed the samples in 71 a vacuum drying oven at 120 °C for 24 hours."
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
After the revisions, this manuscript has improved significantly. Therefore this manuscript can be accepted.
Author Response
Thanks.
Reviewer 3 Report
The reised version has been improved and most of the issues have been addressed. Although, some concerns are deserted and should be addressed as follow:
1. The EC of the EIS data should be presented and the corresponding data should be discussed!
2. Some peaks in XRD are missing such as 2theta around 17 degree and etc (Fig. 1)
Author Response
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Author Response File: Author Response.pdf
