Synthesis of Fe2O3/Mn2O3 Nanocomposites and Impregnated Porous Silicates for Dye Removal: Insights into Treatment Mechanisms
Round 1
Reviewer 1 Report
In this manuscript, the authors prepared porous materials supported by bimetallic nanoparticles, i.e. Fe2O3/Mn2O3@SiO2, to remove dye via photo-Fenton reaction. Fe2O3/Mn2O3@SiO2 exhibited a better removal ability of cationic dye, which was mainly ascribed to the synergistic role of adsorption, Fenton reaction, and photocatalysis process. Furthermore, the explanation of mechanism was clear. Prior to the consideration of publication, some issues needed to be revised and added. Based on the above fact, a small revision to this manuscript is suggested for publication in Catalyst.
Some specific problems are listed as follows:
1. Line 64 page 2,“However, photocatalytic degradation cannot occur in the absence of adsorption”. Herein, the references should be provided.
2. The manuscript should be carefully checked, for example, the caption in Figure 1 is inconsistent with the statement in section 3.1.1.
3. Line 64 page 2, “FM-NPs have an amorphous coral-like shape” should be “FM-NPs have a coral-like shape”. XRD pattern showed that FM-NPs had a good crystal structure.
4. The XPS analyzes of the synthesized Fe2O3/Mn2O3@SiO2 (FMS) should be added in the manuscript, in order to further illustrate the existence of Fe2O3/Mn2O3 nanocomposites on the SiO2. Relevant reference including ACS Energy Letters 6.9 (2021): 3011-3019; should be considered for a soload analysis.
5. It’s better to add the zeta potential of Fe2O3/Mn2O3@SiO2, which can further confirm the negatively charged surface of materials at a pH of 7.
6. Please repeat the tests of dye degradation procedure.
7. The experimental details of 'UV only' (Figure 6d and 7d) need be stated. How did the author shield the interference of FMS on dye adsorption?
8. Recently, there have been many articles related to this field or electrode materials, such as: Chemosphere 302 (2022): 134849; Chemical Engineering Journal 390 (2020): 124643; Chemical Engineering Journal 430 (2022): 132829; which need to be considered.
Author Response
Responses to the reviewers’ comments
First, we would like to acknowledge the editor and the reviewers for their time in reviewing this manuscript and thank them for their constructive comments. We have carefully addressed all issues raised by the reviewers, as evidenced in the following point-by-point responses to the reviewers’ comments; we believe that these adjustments have significantly improved our manuscript. Please refer to our revised manuscript in the attachment.
Reviewers' comments:
Reviewer #1: In this manuscript, the authors prepared porous materials supported by bimetallic nanoparticles, i.e. Fe2O3/Mn2O3@SiO2, to remove dye via photo-Fenton reaction. Fe2O3/Mn2O3@SiO2 exhibited a better removal ability of cationic dye, which was mainly ascribed to the synergistic role of adsorption, Fenton reaction, and photocatalysis process. Furthermore, the explanation of mechanism was clear. Prior to the consideration of publication, some issues needed to be revised and added. Based on the above fact, a small revision to this manuscript is suggested for publication in Catalyst.
Some specific problems are listed as follows:
Comment 1. Line 64 page 2, “However, photocatalytic degradation cannot occur in the absence of adsorption”. Herein, the references should be provided.
→Response: The references were provided accordingly in the manuscript. (Line 67)
Comment 2. The manuscript should be carefully checked, for example, the caption in Figure 1 is inconsistent with the statement in section 3.1.1.
→Response: As suggested by the reviewer, the caption in Figure 1 is revised as follows, (Line 114).
Comment 3. Line 64 page 2, “FM-NPs have an amorphous coral-like shape” should be “FM-NPs have a coral-like shape”. XRD pattern showed that FM-NPs had a good crystal structure. Line 143 page 4, FM-NPs have a crystalline coral-like shape
→Response: Thank you for the correction. As suggested by the reviewer, the manuscript has been revised. (Line 103)
Comment 4. The XPS analyzes of the synthesized Fe2O3/Mn2O3@SiO2 (FMS) should be added in the manuscript, in order to further illustrate the existence of Fe2O3/Mn2O3 nanocomposites on the SiO2. Relevant reference including ACS Energy Letters 6.9 (2021): 3011-3019; should be considered for a soload analysis.
→Response: The XPS analysis has been done for the synthesized Fe2O3/Mn2O3@SiO2 (FMS), and the results (figure 6) were added to the manuscript. (Line 171).
Comment 5. It’s better to add the zeta potential of Fe2O3/Mn2O3@SiO2, which can further confirm the negatively charged surface of materials at a pH of 7.
→Response: Thank you for the good suggestion. To supply more information about the surface charge, zeta potential of FMS in different pH conditions were analyzed. Please see Figure 8 and Line 232.
Comment 6. Please repeat the tests of dye degradation procedure.
→Response: All dye degradation experiments were performed in a duplicate, and the results represent an average value. We revised the manuscript with additional information in line 416.
Comment 7. The experimental details of 'UV only' (Figure 6d and 7d) need be stated. How did the author shield the interference of FMS on dye adsorption?
→Response: ‘UV only’ in Figure 6d and 7d means experiment under ‘Photolysis’ condition without adding adsorbent. In the results, photolysis (UV only) showed 42% removal of dye by photons. This may be due to the cleaved H2O generating hydroxyl radicals which can interact with target molecule of dye. To make it clear, Figure 6d, and 7d has been revised, and additional information was added in the manuscript. (Line 257)
Comment 8. Recently, there have been many articles related to this field or electrode materials, such as: Chemosphere 302 (2022): 134849; Chemical Engineering Journal 390 (2020): 124643; Chemical Engineering Journal 430 (2022): 132829; which need to be considered.
→Response: Thank you for the recommendation of interesting articles. Some of articles that you recommended were considered as references in the manuscript.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript titled " Synthesis of Fe2O3/Mn2O3 nanocomposites and impregnated porous silicates for dye removal: Insights into treatment mechanisms"
In this manuscript, the authors successfully prepared Fe2O3/Mn2O3 nanocomposites and impregnated porous silicates (Fe2O3/Mn2O3@SiO2 [FMS]) and investigated as catalytic adsorbents. The accomplished samples performance is impressive. Therefore, I would like to recommend published this work after addressing the following points:
1. Introduction is well-organized and well-written, but the importance and novelty of the research should be highlighted and more clearly stated. The authors give some examples of works in the bibliography, but which is the advantage of their work in comparison with those works.
2. The authors are responsible for the English, which should be polished throughout the manuscript to clear some minor typo/grammar errors.
3. In the introduction part, Some publications are suggested to refer to improve the quality of the manuscript, such as: https://doi.org/10.1016/j.catcom.2022.106479, https://doi.org/10.1016/j.jtice.2021.08.034, https://doi.org/10.1021/acsomega.1c03693.
4. All equations should be revised in the manuscript, which contain some typo error.
5. The author should better improve the beauty and quality of the figures in the manuscript.
6. In experimental section, please provide the purity of your chosen precursors.
7. In experimental section, the conditions used for all characterization techniques should be added.
8. Author Should provide more information about the preparation technique, in which the procedure of the method used is not unclear.
Author Response
Responses to the reviewers’ comments
First, we would like to acknowledge the editor and the reviewers for their time in reviewing this manuscript and thank them for their constructive comments. We have carefully addressed all issues raised by the reviewers, as evidenced in the following point-by-point responses to the reviewers’ comments; we believe that these adjustments have significantly improved our manuscript. Please refer to our revised manuscript in the attachment.
Reviewer #2: The manuscript titled " Synthesis of Fe2O3/Mn2O3 nanocomposites and impregnated porous silicates for dye removal: Insights into treatment mechanisms"
In this manuscript, the authors successfully prepared Fe2O3/Mn2O3 nanocomposites and impregnated porous silicates (Fe2O3/Mn2O3@SiO2 [FMS]) and investigated as catalytic adsorbents. The accomplished samples performance is impressive. Therefore, I would like to recommend published this work after addressing the following points:
Comment 1. Introduction is well-organized and well-written, but the importance and novelty of the research should be highlighted and more clearly stated. The authors give some examples of works in the bibliography, but which is the advantage of their work in comparison with those works.
→Response: Thank you for your constructive suggestions. The novelty of this research was highlighted in the manuscript as follows. (Line 78~)
Comment 2. The authors are responsible for the English, which should be polished throughout the manuscript to clear some minor typo/grammar errors.
→Response: Words, typo, and grammar errors have been properly corrected in the manuscript.
Comment 3. In the introduction part, Some publications are suggested to refer to improve the quality of the manuscript, such as: https://doi.org/10.1016/j.catcom.2022.106479, https://doi.org/10.1016/j.jtice.2021.08.034, https://doi.org/10.1021/acsomega.1c03693.
→Response: Thank you for the recommendation of interesting articles. Two articles that you recommended were considered as references in the manuscript.
Comment 4. All equations should be revised in the manuscript, which contain some typo error. -> eq.9
→Response: All equations were double checked throughout the manuscript, and Eq.9 was revised in the manuscript (Line 415).
Comment 5. The author should better improve the beauty and quality of the figures in the manuscript. →Response: Figure 1, Figure 2, Figure 6, Figure 7, Figure 8, Figure 9 were revised to improve the quality and clarity in the manuscript.
Comment 6. In experimental section, please provide the purity of your chosen precursors.
→Response: In section 3.1. and 3.4., the purity of chemical products has been included as follows. (Line 364~, 404)
Comment 7. In experimental section, the conditions used for all characterization techniques should be added.
→Response: In section 3.3., the condition for characterization has been revised, and XPS was also added as follows (Line 383-400).
Comment 8. Author Should provide more information about the preparation technique, in which the procedure of the method used is not unclear.
→Response: All preparation techniques for synthesis of catalysts used in this manuscript is stated in section 3.2., and the section 3 (materials and method) has been thoroughly revised.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Accepted in the present form
