One-Step Preparation of High Performance TiO₂/CNT/CQD Nanocomposites Bactericidal Coating with Ultrasonic Radiation

Round 1

Reviewer 1 Report

·             Improve the introduction. Include additional references that are current (less than 5 years old) there are 0 of 9 references that are less than 5 years old Investigation on the effect of functionalization of single-walled carbon nanotubes on the mechanical properties of epoxy glass composites: experimental and molecular dynamics … Experimental measurement and simulation of mechanical strength and biological behavior of porous bony scaffold coated with alginate-hydroxyapatite for femoral applications Lead removal from aqueous medium using fruit peels and polyaniline composites in aqueous and non-aqueous solvents in the presence of polyethylene glycol Experimental investigation of machinability in laser-assisted machining of aluminum-based nanocomposites Longitudinal vibration and instabilities of carbon nanotubes conveying fluid considering size effects of nanoflow and nanostructure

·             Improve the size of the figures, include more descriptive captions for all figures, make sure there is a detailed discussion of the figures

·             The paper should be carefully revised for punctuation, grammar, spelling mistakes and sentences structuring.

·             The Abstract should contain answers to the following questions: What problem was studied and why is it important? What methods were used? What are the important results? What conclusions can be drawn from the results? What is the novelty of the work and where does it go beyond previous efforts in the literature? Add the main findings and objective of the current study in the abstract.

·             Modify the 'Conclusion' section. It should be specific. Restate the hypothesis briefly and summarize the key findings throughout with further applications

·             The lack of physical argumentation is a concern that should be rectified in the revised version.

·             The Introduction should make a compelling case for why the study is useful along with a clear statement of its novelty or originality by providing relevant information and providing answers to basic questions such as: What is already known in the open literature? What is missing (i.e., research gaps)? What needs to be done, why and how? Clear statements of the novelty of the work should also appear briefly in the Abstract and Conclusions sections.

·             The manuscript has full of grammatical errors/ typos/ incomplete sentences and non-relative phrases. The manuscript needs to be checked by both a native English speaking and an expert in biomedical engineering field.

·             There is no objective for this study, since nothing has been mentioned at the end of Introduction section.

·             The format of typesetting is not standardized. In addition, the language description needs to be improved

Author Response

Dear Editor:

      Thank you for your letter and for the reviewers’ comments concerning our manuscript. Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. Revised portion are marked in red in the paper.  The responds to the reviewer’s comments are "in the attachment".

Author Response File: Author Response.pdf

Reviewer 2 Report

Thank you for the opportunity to review this paper. This is an exciting piece of work considering that it aims was to prepared sol with tetrabutyl titanate; commercial P25 TiO2 was added to ensure the uniformity of nanoparticles; and CNT and CQD were doped to improve the light absorptivity of semi-conductive materials. Despite the hard work collecting data in this manuscript,  I do not think this present version is good enough to be published in COATINGS.

·         The Introduction section is too short and sometimes vague (remove any conclusion like the last sentence); it must be rewritten to be better understood by a broad audience.

·         M&M, section 2.2: must be completely rewritten with the operational information (current, vacuum, etc.) related to all tools used in the experiments. Why is the XPS not included in this section?

·         Results and discussion.

o   The quality of figures 2 and 5 are not acceptable.

o   There is no shift in the XPS peak as indicated in Linea 116-119. Please provide a piece of clear evidence for these statements.

o   The whole section is very shallow. There is much more to explore from all the tests. Please provide profound research on the literature data and compare it with your results.  

·          Please provide the implications of your results for the clinical level (especially related to TiO2 /CNT/CQD biocompatibility), the limitations of your project, and recommendations for future works.

Author Response

Dear Editor:

      Thank you for your letter and for the reviewers’ comments concerning our manuscript. Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. Revised portion are marked in red in the paper.  The responds to the reviewer’s comments are "in the attachment".

Author Response File: Author Response.pdf

Reviewer 3 Report

 In this research, a novel mesoporous composite was obtained by doping carbon nanotubes (CNT) and carbon quantum dots (CQD) with tetrabutyltitanate and P25 TiO₂ under ultrasonic radiation. This nanocomposite was shown to eliminate Escherichia coli (EC) and to have good photoelectric properties, thus being able to represent a considerable opportunity for industrial applications. The same nanocomposite was characterized for surface area and its morphology as well as for pore width and microstructure.

Introduction deals with TiO₂ materials considering their relevance for photo-catalytic reactions and photo-electrochemical processes. In this respect, it appears to be crucial the development of a TiO₂-based photo-catalyst that is responsive to the visible light.

Experimental section includes: a) Synthesis (formation) of the TiO₂/CNT/CQD composite b) Characterization of this composite (by TEM, XRD, XPS, EDS, UV-vis and fluorescence spectrophotometry)  c) Test of antibacterial activity of  the same composite against EC d) Evaluation of the photo-electrochemical properties of the above composite.

Results are reported correctly and conclusions are in line with the obtained experimental evidences.

This paper is somewhat interesting and adequately planned. The experiments appear to have been performed by suitable methodologies and executed by qualified technical competence. However, Authors should revise sentence-by-sentence the manuscript since there is a myriad of minor inaccuracies of language whose resolution will improve both appreciation and undoubted validity of the present study. For example:

-      line 20 and 87:…the bacterium of Escherichia coli…=…Escherichia  coli  bacteria…

-      line 21:…exhibit…=…exhibits…

-      lines 30-31:… to arrange the nanoscale,…= (? Please explain better) … that can site-selective coupling of different materials…=…that can site-selectively couple different materials…

-      line 38:…to achieve…= …(? Please explain better).

-      lines 50 and 71:…, sol…= solution?...

-      line 56:…, ethanol absolute…= …and ethanol absolute

-      line 61-62: GQD…=…CQD…

-      line 107:…a useful…=…an useful…

-      line 110:…It attributes…=…, being this property attributable to….

-      and so on.

Moreover, several journal titles in References should be adequately abbreviated. For example:

(2) Trends Biotechnol.  (7, 13) Int. J. Electrochem. Sci.  (9) Ind. Eng. Chem. Res. (17, 20) J. Phys. Chem. (27) Chem. Comm.  (28) J. Am. Chem. Soc. (36) Int. J. Mol. Sci….and so on.

References are updated and adequate. The five figures appear to be explanatory, while their legends could be a little condensed. 

Author Response

Dear Editor:

      Thank you for your letter and for the reviewers’ comments concerning our manuscript. Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. Revised portion are marked in red in the paper.  The responds to the reviewer’s comments are "in the attachment".

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The requests were only partially addressed.

I cannot agree with an introduction that brings a conclusion statement, as in l. 69.  Please remove it. 

Section 2.2 Characterization is still incomplete. Provide all the technical parameters for each equipment used in your experiment because they can impact your results. 

Author Response

Please see the attachment

Author Response File: Author Response.doc