Bimetal CuFe Nanoparticles—Synthesis, Properties, and Applications
Round 1
Reviewer 1 Report
Overview:
The author provides a review article covering the synthesis and applications of FeCu nanoparticles. While there have been numerous studies published for FeCu nanomaterials, there is a general lack of review articles on these materials and this article represents an opportunity to provide a current update. Overall, the article is generally well written and presented in a logical order. With minor revisions, this manuscript will be appropriate for publication. The following comments are offered to strengthen the quality of the final manuscript.
General Comments:
Line 26: Recommend “3d” be clarified as “3rd period”
Figure 1: Consider lighter background color to increase contrast.
Line 75: The sentence, “The CuFe bimetallic nanoparticles can be oriented in alloy” should be accompanied by a supporting citation.
Line 76-78: This sentence also needs a reference.
Line 94: “FeCu’ “ – I don’t think the apostrophe should be included.
Sections 2 and 3: Sub section headers might be useful and allow the reader to quickly access the information of interest: ie Modeling, Synthesis, ORR, Catalysis, etc
Figure 5: It appears that this figure caption sentence should describe panel (e). Figure panel (e) is the same as (d) and does not depict magnetization and coercivity.
Line 159-160: What are the ductility values for comparison?
Line 163: Recommend “maxim” be changed to “maximum”
Line 192: It is unclear what the weight percents refer to.
Line 207: Recommend, “and is average twice as large” be reworded to “and is twice as large on average . . .”
Figure 6: “nZVI” in the caption is not defined as an acronym and not discussed in the main body of the paper.
Line 240-242: Multiple superscripts missing on Fe valence and ion charges.
Line 256-257: Mechanical and catalytic properties were not discussed in Section 2.
Line 290: Should “absorption” be “adsorption”?
Line 330/337: “Cr6+” needs superscript
Figure 11: Figure is difficult to read based on small size.
Line 366-376: This list seems disjointed from the Section application discussion. Mesoporous structures are not fully addressed in either synthesis or application sections.
Line 380: “balk” should be “bulk?
Conclusion: For the challenge of nanoparticle oxidation, which techniques look most promising? Which have been less effective?
Author Response
Dear Reviewer,
Thank you very much for valuable comments to my manuscript entitled: "Bimetal CuFe nanoparticles – synthesis, properties, and applications."
The points raised by the reviewers have been answered and the relevant changes in the revised manuscript are highlighted with yellow colour.
Please find below my explanation and revision responding to the comments. I sincerely hope that my corrections are satisfactory and manuscript will be considered for publication in Applied Sciences.
Line 26: Recommend “3d” be clarified as “3rd period”
It was changed.
Figure 1: Consider lighter background color to increase contrast.
The figure 1 was changed.
Line 75: The sentence, “The CuFe bimetallic nanoparticles can be oriented in alloy” should be accompanied by a supporting citation.
References were added.
Line 76-78: This sentence also needs a reference.
References were added.
Line 94: “FeCu’ “ – I don’t think the apostrophe should be included.
It was changed.
Sections 2 and 3: Sub section headers might be useful and allow the reader to quickly access the information of interest: ie Modeling, Synthesis, ORR, Catalysis, etc
Subsections were added.
Figure 5: It appears that this figure caption sentence should describe panel (e). Figure panel (e) is the same as (d) and does not depict magnetization and coercivity.
Figure 5 was corrected.
Line 159-160: What are the ductility values for comparison?
The ductility values for comparison were added:
The compressive yield stress of FeCu is 720 MPa, while for Fe nanopowder (30 nm) -1100 MPa.
Line 163: Recommend “maxim” be changed to “maximum”
It was changed.
Line 192: It is unclear what the weight percents refer to.
It was corrected.
Line 207: Recommend, “and is average twice as large” be reworded to “and is twice as large on average . . .”
It was changed.
Figure 6: “nZVI” in the caption is not defined as an acronym and not discussed in the main body of the paper.
In Introduction section was added information about nZVI:
Nanoscale zero-valence iron (nZVI) is a strong reducing agent. A large specific surface area and reactivity of these nanoparticles increase the efficiency of removing inorganic and organic pollutants as well as heavy metals. However, due to their small size and magnetic properties, they easily aggregate [14-17].
Line 240-242: Multiple superscripts missing on Fe valence and ion charges.
It was corrected.
Line 256-257: Mechanical and catalytic properties were not discussed in Section 2.
In Section 2 was shown, that structure depends mainly on the concentration of Cu and Fe in the particles, and mechanical, catalytical, and magnetic properties depend on the structure and composition, and also on the additions such as carbon, graphite or silicon used for supporting the created nanoparticles. For example . With the increasing of the CNT content in CuFe/CNT nanocomposites, agglomerates size decreased, while coercivity, magnetization, and electrical resistivity of composite samples increased.
Line 290: Should “absorption” be “adsorption”?
It was corrected.
Line 330/337: “Cr6+” needs superscript
It was corrected.
Figure 11: Figure is difficult to read based on small size.
Figure 11 was enlarged.
Line 366-376: This list seems disjointed from the Section application discussion. Mesoporous structures are not fully addressed in either synthesis or application sections.
Information about mesoporous materials and their role in CuFe/mesoporous structure composites were added:
To increase the catalytic activity of the catalysts, porous materials such as mesoporous silica, activated carbon, mesoporous carbon and carbon nanotubes are also used. Compounds such as phenol, benzoic acid, bisphenol A, 2,4,6-trichlorophenol, imidacloprid, ketoprofen, methylene blue, and methyl orange have been effectively removed from water using CuFe nanoparticles dispersed on mesoporous carbon (CuFe-MC) [61]. The high specific surface area of mesoporous materials increases the absorption of pollutants.
Line 380: “balk” should be “bulk?
It was corrected.
Conclusion: For the challenge of nanoparticle oxidation, which techniques look most promising? Which have been less effective?
Conclusion section was extended:
For the challenge of nanoparticle oxidation two techniques seem promising, combination of a chemical reduction of ferric nitrate and copper nitrate in alcohol solution with annealing carbonization technique, and a high temperature pyrolysis of the copper precursor (chlorophyllin) and the iron precursor (Fe(II) acetylacetonate). While the reduction of copper and iron sulfides with sodium borohydride, and reduction of cupric and ferric nitrates with sodium borohydride in ethylene glycol under Ar seem to be less effective.
I hope that the revised manuscript is now acceptable for publication in Applied Sciences.
Sincerely yours,
Zaneta Swiatkowska-Warkocka
Reviewer 2 Report
This review on Fe-Cu nanoparticles is well received because of the growing interest in earth abundant alloy nanoparticles for catalytic applications, as well as abut the strategies for their stabilization against chemical transformation. The text is fluent, the main features of the Cu-Fe system are clearly described and figures are clear and well chosen. I recommend publication after minor revisions:
Instead of “high corrosion resistance” of Cu, I would say “appreciable” considering its cost.
Figure 3a: meaning of DFe is unclear, should be D(Fe-Cu) or what?
The role of traces of iron oxide on the magnetic properties of the nps should be commented more explicitly, as this is systematically present at ambient conditions, at least on particles surface.
More comments on stabilization of surface oxidation may be useful
Please explain the meaning of “smelting wastewater” for the general reader.
Copper is not “cheap” but non-precious or earth-abundant
Author Response
Dear Reviewer,
Thank you very much for valuable comments to my manuscript entitled: "Bimetal CuFe nanoparticles – synthesis, properties, and applications."
The points raised by the reviewers have been answered and the relevant changes in the revised manuscript are highlighted with yellow colour.
Please find below my explanation and revision responding to the comments. I sincerely hope that my corrections are satisfactory and manuscript will be considered for publication in Applied Sciences.
Instead of “high corrosion resistance” of Cu, I would say “appreciable” considering its cost.
It was changed.
Figure 3a: meaning of DFe is unclear, should be D(Fe-Cu) or what?
In paper [26] authors examined three Fe cores (DFe) with diameters 5, 7, and 9 nm with respective Cu concentrations. Explanation was added in main text and description of Fig.3a
The role of traces of iron oxide on the magnetic properties of the nps should be commented more explicitly, as this is systematically present at ambient conditions, at least on particles surface.
The role of iron oxides on the magnetic properties of nanoparticles was commented in section 2 of manuscript:
At this point, it should be emphasized that the properties, and in particular the magnetic properties of the synthesized materials, depend not only on the size, shape, structure, but most of all on the composition of the synthesized materials. The presence of iron oxides in nanoparticles influences its magnetic properties and can change saturation magnetization, coercivity, blocking temperature and relaxation time, and thus may limit their use [56].
More comments on stabilization of surface oxidation may be useful
More comments on stabilization was added.
Please explain the meaning of “smelting wastewater” for the general reader.
Explanation of the “smelting wastewater” was added:
wastewater produced from smelting, the extraction of metal from its ore by a process involving heating and melting.
Copper is not “cheap” but non-precious or earth-abundant
It was changed.
I hope that the revised manuscript is now acceptable for publication in Applied Sciences.
Sincerely yours,
Zaneta Swiatkowska-Warkocka
