Electroless Deposits of ZnO and Hybrid ZnO/Ag Nanoparticles on Mg-Ca0.3 Alloy Surface: Multiscale Characterization
Round 1
Reviewer 1 Report
In this manuscript C. J. Luis et al. reported the deposition of ZnO and ZnO/Ag nanostructures on the Mg-Ca alloy surface obtained from different aqueous precursor solutions. The surface was carefully characterized by SEM, EDS, XPS, FTIR, and UV-Visible and Raman spectroscopy. The electroless deposition might be interesting for the fabrication of antibacterial surfaces, however, the novelty of the manuscript is unclear. ZnO or Zn/Ag as antibacterial coating on alloy surface has been extensively studied (e.g., Materials Science and Engineering: C 2020, 114, 110997), therefore, it is unclear what the present study contributes to this research field. Even though the present study tried to focus on the characterization of the coating, discussions are still highly needed to differentiate this work from the previous studies on ZnO and ZnO/Ag coatings. Additionally, more insights should be provided to strengthen the science of the present work. Furthermore, the following points should be addressed satisfactorily before the manuscript could be further considered for publication.
1. XRD characterization of the surfaces should be provided to identify the coating structure.
2. Figure 2: carbon content in the coating obtained from ZnO solution looks much higher than that from Zn(NO3)2 solution; it would be better to discuss the reason.
3. Figure 4: How about the thickness of ZnO coatings from ZnO and Zn(NO3)2 solutions? Such information is important because it is strongly correlated to the Zn concentration in the coating.
4. Figure 5: it is hard to see the individual particle in the present images. Images with higher magnification should be provided.
5. Table 2 is missing.
6. The authors hypothesized that Mg-Ca could facilitate the Ag deposition, so Mg-Ca surface might undergo corrosion during the reduction of Ag ions. It would be better to discuss it.
7. There appeared some carbonates in the coating. How would they affect the antibacterial property? It would be helpful to discuss the effect of carbonates.
Author Response
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Reviewer 2 Report
The manuscript presents an interesting study about the electroless coatings based on ZnO and ZnO/Ag deposited on the surface of an Mg-Ca alloy. The characteristics of the coatings were studied by SEM, XPS, FTIR etc. The paper needs major revisions before it is processed further, some comments follow:
Abstract:
The abstract must be improved. Please highlight the novelty of the study
Introduction:
The introduction section must be improved. In the introduction section, a comprehensive and exhaustive review of the state of the art in the field of the study must be provided. Please discuss more previous works and highlight the previous experiments and results.
Also, multiple citations have been introduced in bulk form "[1-10]", "[11-18]", "[19-21]", "[22-27]", "[27-34]", "[43-48]" , "[50-54]" , "[55-67]", "[61-64]", "[72-74]" "[77-80]", "[81-85]" , "[86-88]" , "[94-99]" , "[107-112]" and not distributed in the text by the affirmations that must be supported. Please introduce citations in a specific position to ensure clear correspondence between the affirmations from the introduction section and the previous publication. Moreover, to avoid this type of citing, please cite review type of studies.
Results and discussion
Figures 1, 2, 3, 9, 10, and 11 are not clear, please replace them.
References
Are too many references, please remove the unnecessary ones.
Author Response
In attach.file we send your responses to your comments and suggestions.
We appreciate your time, giving us a possibility to improve our manuscript.
Author Response File: Author Response.pdf
Reviewer 3 Report
The present work studies electroless deposits of ZnO and hybrid ZnO/Ag nanoparticles on the surface of the Mg-Ca0.3 alloy. Overall the work is written to a good standard and is well outlined. However, some urgent improvements are needed before publication.
Improvement suggestions:
i) It is essential to add a sentence in the Introduction reinforcing the importance and relevance of the work:
ii) All Figures need better care in editing, some have low quality, and others are tiny:
iii) There is a severe problem in the Results and Discussions section. Basically, the results are presented with very superficial discussions. Therefore, I suggest that the discussions are best explained with a direct link between the characterization techniques;
iv) Finally, the conclusion should be improved in line with the improvements made in the Results and Discussions section.
Author Response
In attach.file we send your responses to your comments and suggestions.
We appreciate your time, giving us a possibility to improve our manuscript.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors have addressed my comments. The manuscript can be accepted in present form.
Reviewer 2 Report
The paper can be published in the present form.
Reviewer 3 Report
The authors made all the suggested modifications. Therefore, the article can be accepted for publication in its present form.
