Plasma Electrochemical Synthesis of Graphene-Phosphorene Composite and Its Catalytic Activity towards Hydrogen Evolution Reaction
, Vladimir P. Vasiliev * and Alexander G. KrivenkoRound 1
Reviewer 1 Report
I would like to suggest the author with major revision for this manuscript. Please check the file below for more detail.
Comments for author File: 
Comments.pdf
Author Response
First of all, we would like to thank reviewer for deep and thorough reading and very helpful remarks, suggestions and comments. They helped us to enhance the quality of our manuscript.
Remark: 1. The abstract is very simple. The hydrogen reaction efficiency with quantitative value should be provided. The noble in structure of graphene-phosphorene also need to be provided.
Response: We agree with reviewer’s remark. Corresponding changes were introduced in the manuscript.
Remark: 2. In the introduction part, the summary in the hydrogen evolution reaction condition should be provide for potential reader to get a little bit more detail about the study condition.
Response: We agree with reviewer’s remark. Corresponding changes were introduced in the manuscript.
Remark: 3. The source of materials (red phosphorus, ethylenediamine, Na2SO4 graphene, etc) need to be listed in detail (company, purity).
Response: We agree with reviewer’s remark. Corresponding changes were introduced in the manuscript.
Remark: 4. Figure 2, the scale bar should be added for better visual aids. The grain or boundary should be added to show up each component of either graphene or phosphorene.
Response: We agree with reviewer’s remark. Corresponding changes were introduced in the manuscript.
Remark: 5. Raman spectra should be added to define the defect of graphene sheets, and the composite.
Response: Previously in our works, Raman spectra were presented for few-layer graphene structures obtained via plasma-electrochemical method. These spectra were analyzed and conclusions were made about the defectiveness of synthesized structures [R1]. Unfortunately at present, we do not have the opportunity to carry out such measurements, but these studies are planned to be carried out in the future.
R1. Kotkin, A.S.; Kochergin, V.K.; Kabachkov, E.N.; Shulga, Y.M.; Lobach, A.S.; Manzhos, R.A.; Krivenko, A.G. One-step plasma electrochemical synthesis and oxygen electrocatalysis of nanocomposite of few-layer graphene structures with cobalt oxides. Mater. Today Energy 2020, 17, 100459. [https://doi.org/10.1016/j.mtener.2020.100459]
Remark: 6. The quantitative values on hydrogen evolution of FLGS, GPS, and GPS/FLGS should be added and discussed in more detail. In addition, the mechanism behind the rapid improving in catalytic activity of GPS/FLGS is needed with detail explanation. The simple reason on the higher conductivity is not sufficient.
Response: We agree with reviewer’s remarks. Corresponding changes were introduced in the manuscript.
Remark: 7. The conclusion must be re-written, I saw no difference between the abstract and the conclusion part. Please write it again.
Response: We agree with reviewer’s remark. Corresponding changes were introduced in the manuscript.
Remark: 8. Please recheck the spelling and grammar again.
Response: We agree with reviewer’s remark. We have thoroughly read the manuscript and checked the spelling and did our best to improve the grammar. Corresponding changes were introduced in the manuscript.
Author Response File: Author Response.pdf
Reviewer 2 Report
In this work, the plasma-assisted electrochemical method was developed to fabricate the graphene-phosphorene structures for hydrogen evolution reaction (HER). scanning electron microscopy (SEM) and X-ray photoelectron spectros-copy (XPS) were employed to explore the structure of the as-prepared samples. And, the electrochemical test showed the HER activity for GPS/FLGS can be greatly enhanced compared with FLGS and GPS. Therefore, I recommend it publish after addressing the following issues.
1. These most recently reported literature should be cited to support the statement “……combination of phosphorene with other active materials [10,11], such as MoS2 and Ni2P” in the introduction part,: Adv. Mater. 2022, 34, 5397-5406; Adv. Mater. 2022, doi.org/10.1002/adma.202206828.
2. I noticed that the used reference is Pt foil. However, the Pt will be deposited on the cathode if the electrolysis period is long enough. I would suggest the authors re-test the HER performance by using a graphite rod as reference electrode.
3. How about the stability of the as-prepared catalysts?
4. The Tafel slopes should be obtained to evaluate the kinetics of the as-prepared samples.
Author Response
First of all, we would like to thank reviewer for deep and thorough reading and very helpful remarks, suggestions and comments. They helped us to enhance the quality of our manuscript.
Remark: 1. These most recently reported literature should be cited to support the statement “……combination of phosphorene with other active materials [10,11], such as MoS2 and Ni2P” in the introduction part,: Adv. Mater. 2022, 34, 5397-5406; Adv. Mater. 2022, doi.org/10.1002/adma.202206828.
Response: We agree with reviewer’s remark. Corresponding changes were introduced in the manuscript and recommended references were cited.
Remark: 2. I noticed that the used reference is Pt foil. However, the Pt will be deposited on the cathode if the electrolysis period is long enough. I would suggest the authors re-test the HER performance by using a graphite rod as reference electrode.
Response: Measurements of electrochemical characteristics of synthesized catalysts were carried out within the potential range where no dissolution nor sputtering of Pt counter electrode took place. Besides, during electrochemical measurements, no change in the electrocatalytic activity of the catalysts was observed. It was demonstrated earlier in our works [R1–R3], so the results obtained in this work are beyond doubt.
R1. Vasiliev, V.P.; Kotkin, A.S.; Kochergin, V.K.; Manzhos, R.A.; Krivenko, A.G. Oxygen reduction reaction at few-layer graphene structures obtained via plasma-assisted electrochemical exfoliation of graphite. J. Electroanal. Chem. 2019, 851, 113440. [https://doi.org/10.1016/j.jelechem.2019.113440]
R2. Kotkin, A.S.; Kochergin, V.K.; Kabachkov, E.N.; Shulga, Y.M.; Lobach, A.S.; Manzhos, R.A.; Krivenko, A.G. One-step plasma electrochemical synthesis and oxygen electrocatalysis of nanocomposite of few-layer graphene structures with cobalt oxides. Mater. Today Energy 2020, 17, 100459. [https://doi.org/10.1016/j.mtener.2020.100459]
R3. Krivenko, A.G.; Manzhos, R.A.; Fishgoit, L.A.; Kochergin, V.K. The bipolar mode of one-step plasma electrochemical synthesis of few layer graphene structures decorated with transition metal oxides. ChemistrySelect 2021, 6, 13642–13646. [https://doi.org/10.1002/slct.202103830]
Remark: 3. How about the stability of the as-prepared catalysts?
Response: No doubt stability and durability are the most important characteristics of catalysts. Unfortunately at present, these parameters have not been fully tested and require additional study, which are to be performed and reported in the future.
Remark: 4. The Tafel slopes should be obtained to evaluate the kinetics of the as-prepared samples.
Response: We agree with reviewer’s remark. Corresponding changes were introduced in the manuscript.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I recommended the manuscript for publication as its present form
