Preparation and Properties of Pulsed Composite Coatings of Supercritical Graphene Quantum Dots
Round 1
Reviewer 1 Report
Authors have presented an article entitled “Preparation and Properties of Pulsed Composite Coatings of Supercritical Graphene Quantum Dots” Though the manuscript is well written and organized but there is scope for further improving the quality of the draft before considering for publication.
Detail minor comments are listed below:
1. As the author mentioned, the rapid development of aerospace, automobile, and high-end equipment manufacturing industries, the requirement of coatings is playing a major role. Author should send the performance of these articles to make the contrast: ACS Applied Materials & Interfaces 12 (15), 17988-18001 (2020); Fibers and Polymers 20 (6), 1161-1171 (2019); Journal of Material Science and Mechanical Engineering 2, 58-60. (2015).
2. In Figure 2e, X-axis and Y-axis plot names are not clearly visible. Make it bold and highlighted.
3. Author should use the full name of the abbreviation (like GQD-Graphene Quantum Dots, etc.) when it is used for the first time in any section.
4. In immersion corrosion analysis (Figure 10b), there are some black patches present in the SEM images, which are not visualized in Figure 3d as both samples consist of Ni-GQD-IV. Please elaborate this statement in more detail.
5. Authors should also check the typos and grammatical mistakes in the revised version.
Author Response
Please see the attachment
Author Response File: 
Author Response.docx
Reviewer 2 Report
The article " Preparation and Properties of Pulsed Composite Coatings of Supercritical Graphene Quantum Dots " can be published after major revision.
The main drawback of the manuscript is that the authors do not compare the properties of the composite coatings with Ni-GQD pure nickel. Also, the preparation of the manuscript should be improved based on the MDPI guidelines for authors.
Below are my comments on the article.
1. Line 70 and Table 1 should be H2O instead of H20.
2. In «2. Materials and Methods» please add the thickness of the deposited coatings and agitation rate during electrolysis. The authors did not provide the cathodic current density.
3. In line 183 please correct subsection number 2.1.2. to 3.1.2, and in line 218 from 2.1.3. to 3.1.3.
4. In the description of the microstructure of the obtained composite coatings (lines 159–176) authors should cite the sources describing the mechanism of the particles’ inclusion into the nickel metal matrix.
5. It follows from the text that the deposition was performed onto a copper substrate. Copper is a relatively soft material and for the accurate determination of microhardness thick deposits should be obtained. Did the authors consider this aspect in the measurements?
6. Please improve Fig.6, it is not possible to see the values on axes.
7. The corrosion resistance of the composite coatings must be compared with the pure Ni coating obtained under the same conditions.
8. The authors are right that the embedded second-phase particles can decrease the corrosion resistance of the coatings. However, the second-phase particles can be cathodic regions, while the metal matrix will be anodic. This is well described in https://doi.org/10.3390/ma14206179, https://doi.org/10.1016/j.surfcoat.2019.125063, https://doi.org/10.3390/ma15165550.
9. The results of the electrochemical impedance spectroscopy are poorly described. Please, provide the equivalent circuit used and the results of the spectra fitting.
10. Nyquist plots must have equal-scaled axes, for example, 1 cm= 1000 Ohm.
11. What was the number of parallel experiments in corrosion and microhardness measurements? Please, provide the standard deviation data for all measurements.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Reviewer 3 Report
The manuscript entitled “Preparation and Properties of Pulsed Composite Coatings of Supercritical Graphene Quantum Dots” describes the use of GQDs as additives for composite coatings. In general, the manuscript requires a complete revision to situate the reader bout the frontier in the theme and the advances (the novelty of this work). A Table for comparison of results with data reported in the literature must be provided. A more elaborated discussion about results is necessary.
Abstract: please revise the language, avoiding sentences such as “most excellent mechanical properties” and “so the corrosion resistance is the best.”
What means “reaching 837.6 HV 0.2” ?
It is mL and not ml
More details about sample preparation are required in section 2.1
Figure legends are poorly described. Please revise it.
Legend of Table 4 is incomplete.
Figures are blurry and with poor resolution.
Legends of Figs. 6 and 8 are changed.
The analysis of the results is poorly conducted. As an example, the section “Immersion corrosion analysis” is summarized in one paragraph.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
The paper can be accepted without any further changes.
Reviewer 3 Report
Based on modifications provided by the authors, I consider that manuscript can be accepted as is.
