Nitrogen-Rich Porous Carbon Nanotubes Coated Co/Mo2N Composites Derived from Metal-Organic Framework as Efficient Bifunctional Oxygen Electrocatalysts
Round 1
Reviewer 1 Report
Nitrogen-rich porous carbon nanotubes coated Co/Mo2N composites derived from metal-organic framework as efficient bifunctional oxygen electrocatalysts manuscript is well-written and I recommended it for publication after major revisions. Here are the comments:
1. The authors should note in the Abstract part all techniques of physicochemical characterization of examined samples used in the manuscript (XRD, XPS, TEM, SEM, Raman, and BET).
2. Please, add one paragraph in the Introduction part related to the ORR/OER kinetics parameters (Tafel slope, overpotential, etc.) for similar electrocatalysts. Please, explain their advantages and disadvantages.
3. The authors should increase the size of the letters and numbers inside Fig. 5, Fig. 7, Fig. 8, and Fig. 9. Please, use the same color for one material in all figures for better presenting and understanding resultates.
4. Please, add the scan rate for all measurements in the capture of Fig. 7.
5. The authors should explain all anodic peaks that appeared on CVs in Fig. 7a. Please add the CVs of all three electrocatalysts recorded in the N2-saturated 0.1 M KOH solution in Electronic Supporting Information for a better understanding of anodic peaks.
6. All kinetics ORR parameters (Eonset, E1/2, Tafel slopes, limiting current density, n, etc.) of examined samples should be compared with similar literature reports. Please, show Tafel plots for all electrocatalysts, this figure should be additional Fig. 7f.
7. All kinetics OER parameters (Eonset, overpotential at 10 mA cm-2 (ƞ10), Tafel slopes, etc.) of examined samples should be compared with similar literature reports.
8. Please, compare obtained value for potential difference (ΔE) with similar literature reports.
9. Also, add some ORR and/or OER kinetics parameters (Tafel slope, overpotential, etc.) of the examined samples in the Conclusion part.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
The article "Nitrogen-rich porous carbon nanotubes coated Co/Mo2N composites derived from metal organic framework as efficient bifunctional oxygen electrocatalysts" is devoted to the synthesis of metal-carbon composites used as efficient catalysts for fuel cells. Increasing the activity and stability of catalysts undoubtedly contributes to the widespread development in the field of fuel cells, which are an important component of hydrogen energy. Therefore, the article is of undoubted scientific interest and is enlightened by the actual topic. The materials obtained in the work have been studied in detail by modern methods and their activity for various reactions has been studied in detail. A number of remarks should be noted:
The authors state that» CoMoN@NCNTs series nanomaterials have 100 three characteristic peaks at 44.2°, 51.5° and 74.9°, corresponding to the typical (111), (200) 101 and (220) plane of metallic cobalt respectively». However, these peaks are absent on the diffractogram, which is clearly seen from Figure 1.
The results on the activity of the catalysts should be presented in the form of a table for ease of comparison.
To analyze the impedance, it is necessary to present an equivalent circuit.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Nitrogen-rich porous carbon nanotubes coated Co/Mo2N composites derived from metal-organic framework as efficient bifunctional oxygen electrocatalysts manuscript is well-written and I recommended it for publication after minor revisions. Here are the comments:
1. Please extended an additional paragraph in the Introduction part with a minimum of five new references, two added references are not enough.
2. Please, correct the next sentence:
̏ Each sample has anodic peak and cathodic peak, indicating that the samples prepared at different carbonization temperatures may all show oxygen reduction and oxygen evolution properties. ̏
Part of this sentence related to anodic peaks corresponding to oxygen evolution reaction (OER) is incorrect. The authors should delete this part of the sentence and cut the anodic part of the CVs in Fig. 7a. If the authors decide to leave the anodic part of the CVs, they should find an appropriate explanation for anodic peaks. Please check ref. Nano Res. 2014, 7(7): 1054–1064.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
