Synthesis of SiC/BiOCl Composites and Its Efficient Photocatalytic Activity
Round 1
Reviewer 1 Report
#1. The authors fabricated SiC/BOC composites and analyzed their photocatalytic characteristics. Research results are meaningful in the area of photocatalysis. However, due to the low resolution of figures, it was difficult for me to understand the context of manuscript. The figures in the manuscript should be revised with high resolution.
#2. In the introduction section, it would be better to include the schematic demonstration of BiOCl crystal structure.
#3. In the SEM images(Figure3), it is not easy to understand the differences of structures or surface morphologies of SiC-C-BOC, SiC-G-BOC and SiC-BOC. The SEM images need to be revised. And please insert magnification bars for each image.
#4. From EIS results in Fig 9(b), there are two semicircles for each Nyquist plot. The interface information for each semicircles should be written in the manuscript. If the role of first semicircles is important, the image part of first semicircles in the Nyquist plot need to be enlarged.
#5. The proposed mechanism for the SiC-BOC composite photocatalysis should be enhanced. The explanation for the mechanism is very weak. The mechanism should be elucidated in more detail.
#6. In the experimental section, it would be better to include the detailed procedures for the fabrication of SiC-C and SiC-G. And the explanation for the difference of SiC and SiC-C is not clear.
Author Response
Dear Reviewers：
On behalf of my co-authors, we thank you very much for giving us an opportunity to revise our manuscript, we appreciate editor and reviewers very much for their valuable and detailed comments and suggestions on our manuscript for revising and improving our paper. We have studied comments carefully and have made correction which we hope meet with approval.
The main corrections in the paper and the responds to the reviewer’s comments are as flowing:
Pint 1：
The authors fabricated SiC/BOC composites and analyzed their photocatalytic characteristics. Research results are meaningful in the area of photocatalysis. However, due to the low resolution of figures, it was difficult for me to understand the context of manuscript. The figures in the manuscript should be revised with high resolution.
Response 1：
All the SEM and TEM picture in this paper was replaced by a new one in the revised revision.
Pint 2：
In the introduction section, it would be better to include the schematic demonstration of BiOCl crystal structure.
Response 2：
A Layered structure model illustrations of BiOCl was added in Fig1
Pint 3:
In the SEM images(Figure3), it is not easy to understand the differences of structures or surface morphologies of SiC-C-BOC, SiC-G-BOC and SiC-BOC. The SEM images need to be revised. And please insert magnification bars for each image.
Response 3：
The SEM image has been revised and a lower magnification was offered. The magnification bars was inserted in the new picture.
Pint 4:
From EIS results in Fig 9(b), there are two semicircles for each Nyquist plot. The interface information for each semicircles should be written in the manuscript. If the role of first semicircles is important, the image part of first semicircles in the Nyquist plot need to be enlarged.
Response 4：
A new picture of Nyquist plot was updated and a equivalent circuit model was added whose caculated value was shown in table 2.
Pint 5:
The proposed mechanism for the SiC-BOC composite photocatalysis should be enhanced. The explanation for the mechanism is very weak. The mechanism should be elucidated in more detail. The proposed mechanism for the SiC-BOC composite was rewrited in the rewised version.
Response 5：
The proposed mechanism for the SiC-BOC composite photocatalysis was rewrited in the revised revision
Pint 6:
In the experimental section, it would be better to include the detailed procedures for the fabrication of SiC-C and SiC-G. And the explanation for the difference of SiC and SiC-C is not clear
The detailed procedure for the fabrication of SiC-C and SiC-G was added.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The authors have prepared a novel material based on BiOCl nano sheets grew on a SiC substrate. This could be an interested work, but, under my point of view, more experimental work is required to totally justify authors claims.
For example, it is not clear that they can control de morphology with this synthesis method (hydrothermal). During the SEM and TEM discussion, they are referring to BOC nano sheets, but where are them? where are the nanosheets? How can control the nanostructure and the exposed faces? this is not totally justify.
It is stated that BOC nanostructure increased the amount of reactive sites and advanced the absorption capacity. Due to the morphology and surface area it is expected an enhanced absorption capacity, but how they have calculated the number of reactive sites per nm2?
Author Response
Dear Reviewers：
On behalf of my co-authors, we thank you very much for giving us an opportunity to revise our manuscript, we appreciate editor and reviewers very much for their valuable and detailed comments and suggestions on our manuscript for revising and improving our paper. We have studied comments carefully and have made correction which we hope meet with approval.
The main corrections in the paper and the responds to the reviewer’s comments are as flowing:
Pint 1：
For example, it is not clear that they can control de morphology with this synthesis method (hydrothermal). During the SEM and TEM discussion, they are referring to BOC nano sheets, but where are them? where are the nanosheets? How can control the nanostructure and the exposed faces? this is not totally justify.
Response 1：
The SEM image has been revised and a lower magnification was offered. The description about SEM and TEM results was rewrited.
Pint 2：
It is stated that BOC nanostructure increased the amount of reactive sites and advanced the absorption capacity. Due to the morphology and surface area it is expected an enhanced absorption capacity, but how they have calculated the number of reactive sites per nm2?
It hard to evaluate the reactive site quantitatively. Because the enhanced photocatalytic activities was achieved in two aspect: the quantitiy of oxygen vacancies and the form of carbon on surface of SiC. The area ratio of O2−-BOC to O-BOC (A(OV/OL)) offered a helpful method to evaluate the concentration of oxygen vacancy.The calculated values of A(OV/OL) for SiC-BOC and SiC-G-BOC was 1.37 and 1.06. The enlarged amount of oxygen vacancies in SiC-BOC can be demonstrated by its higher calculated values. But the influence of carbon was hard to caculate, because the form of carbon played a decisive role rather than the contents. The content of carbon was biggest in SiC-G-BOC, but the degradation of TC-HCl was worse than pure BiOCl. So the connection between the reactive sites and surface area can not be analyzed quantitatively.
Round 2
Reviewer 2 Report
I think that the manuscript has been improved in this new version and deserves publication.
