Insight into Anti-Corrosion Behavior and Mechanism of 8-Hydroxyquinoline Inhibitor on AZ91D Alloy in Different Concentrations of Sodium Chloride Solution

Round 1

Reviewer 1 Report

The paper aims to report the anticorrosive behavior and mechanism of 8-hydroxyquinoline in NaCl solution. The authors took a chance and wrote an impressive manuscript. However, before it can be considered for publication, it needs to be further revised according to the following comments.

- The abstract needs to be revised and improved. More interesting information needs to be added to this section.

- Many sentences need to be referenced in the Introduction section.

- The abbreviation AZ91D must be defined the first time it appears. 

- All tables and figures must be mentioned in the appropriate place in the main text.

- A comparison between this study and reported inhibitors for AZ91D surface in the literature must be added and discussed before the Conclusion section.

- In the conclusion, include a section on current research obstacles/challenges and the potential future of this inhibitor for other surfaces.

Many typographical and grammatical errors throughout the text must be corrected.

Author Response

Please see the attachment.

Author Response File: Author Response.doc

Reviewer 2 Report

The authors reported the effect of 8-hydroxyquinoline (8HQ) on the inhibition of AZ91D corrosion in sodium chloride solution. This work is not well written and not well organized and requires major revisions to be reconsidered for publication in coatings. Some of my comments are:-

- The manuscript is not in the format of the COATINGS housestyle.

- The Title must include AZ91D alloy. The title must give a great indication of the content of the manuscript.

- Abstract must be rewritten focusing on the findings and referring to the difference between the effect of the two HQ concentrations.

- Authors should be aware of mentioning the full name before mentioning the abbreviations, I.e. page 1, line 13, SEM should be written in full then the abbreviation should be written as (SEM).

- In the introduction, line 32, "devel-op green and environmentally friendly inhibitors" should be "develop green and environmentally friendly corrosion inhibitors". The word "corrosion" should be attached to the word "inhibitor".

- In line 70, the sentence "on the inhibition and..." must be "on the corrosion inhibition and.....".

- In line 71, "SEM/EDX", the authors must mention the full names of this abbreviation when it is written for the first time in the text.

- Experimental, Materials. What was the exposed area of the test samples (area of your working electrode)? 

- Line 101, authors should provide a reference number cites Equation (1).

- Line 119, Equation (2) there must be a reference for this equation too.

- Line 125, authors mentioned EDS but in line 71, they mentioned EDX, please unify your terms.

- 2.4. Surface morphology and components analysis, please provide the working conditions for the SEM machine.

- Results and Discussion, It is seen that the results are great and figures are well drawn as well as, the Tables are fine. The authors are requested to pay more attention to better discuss the great obtained results.

- References, All references need to be rewritten with the coatings house-style format.

 

The English must be revised and improved. 

Author Response

Please see the attachment.

Author Response File: Author Response.doc

Reviewer 3 Report

The paper represents implementation of several experimental techniques to measure the corrosion progress of Mg alloy in NaCl solution and the influence of 8HQ inhibitor on this process supplemented by some DFT calculations. The positive point is the experimental examination of different concentrations of inhibitor and two concentrations of NaCl in the solution, which can provide a practical guidance. The negative point is a restricted novelty of the results. The experimental conclusions are quite expectable. The DFT part is poorly related with the experimental one: the DFT examines just one 8HQ molecular on magnesium surface without water and NaCl, which can disturb the equilibrium. Therefore, the results of DFT are very limited. I do not see that the obtained experimental and calculation data substantially influence the corrosion-inhibition scenario discussed in the paper. In the case of reconsideration, the authors are requested to substantiate the novelty and discuss the obtained results on the background of existing literature in a separate section. The text is presented inaccurately and does not follow the journal format.

Quality of English is acceptable, but should be checked, for instance, extra "-" signs.

Author Response

Please see the attachment.

Author Response File: Author Response.doc

Round 2

Reviewer 1 Report

Accept in present form

Reviewer 2 Report

The authors have performed the necessary revisions and have greatly improved the manuscript. I believe that their manuscript should be accepted for publication in the present form.

Reviewer 3 Report

I accept the authors' explanations.