Hydrophilicity and Pore Structure Enhancement in Polyurethane/Silk Protein–Bismuth Halide Oxide Composite Films for Photocatalytic Degradation of Dye

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Before being accepted for publication, the submitted manuscript needs a major revision based on the following comments:

1.     In figure 1, the XRD pattern all the corresponding samples are well matched, but author should calculate the crystalline size and dislocation density also. The corresponding values to make discussion to enhance the readers.

2.     Compared to other samples, BiOBr based nanocomposite exhibits excellent photocatalytic activity. Explain what is the mechanism behind it?

3.        In SEM discussion, the author said the particles are agglomeration. What is the reason the particles are agglomerated. Author adds the discussion more in the SEM analysis.

4.     a.u. is not an appropriate abbreviation for arb. units as a.u. stands for astronomical units. Author should be changed.

5.     The authors have conducted the photocatalytic activity of the Rh B dyes at a lab scale only. Why did they not employ real-time samples for the study?

6.     The performance of the process must be evaluated on real wastewater samples at optimal concentration

7.     The author should include information about the light source used for visible-light irradiation, including the wavelength range.

8.     After separating, how to wash the separated catalyst? Or without washing before the next testing runs?

9.     In general, hydroxyl radicals are known to be very strong compared to other radicals. In this study, why do these radicals not exhibit a minor role when using hydroxyl radicals?

 

 

Comments on the Quality of English Language

1Typographical errors are present throughout the manuscript. Authors are required to pay keen attention to this.

Author Response

Thank you very much for taking thetime to review this manuscript. Please find the detailed responses below and the corresponding revisions highlighted in the re-submitted files. 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The following issues must be addressed:

1. The authors must clearly state in the Introduction subchapter what is new and innovative in this work compared with other similar papers;

2. Is not clear why the authors used RhB for this study;

3. TOC of HPLC studies must be included to prove the photocatalytic degradation;

4. The mechanism of RhB degradation was not explained;

5. Include the Miller index planes in the XRD;

6. Which is the radiation intensity (mW/cm2) in the sample proximity?

7. Conclusions should contain the most representative results as well.

Author Response

Thank you very much for taking thetime to review this manuscript. Please find the detailed responses below and the corresponding revisions highlighted in the re-submitted files.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Comments

How did authors obtain 0.2 g of composite film (used for 200 mL of RhB)? By peeling it off from the glass plate?

During the reaction of the composite film with RhB (in the dark and lamp on), did the process involve any magnetic stirring the 200 mL RhB solution with the composite film?

How much aliquot was taken out every 20 min? Did it involve centrifugation to separate the aliquot and the composite film? Please present the procedure in detail.

 

Authors wrote “Therefore, the EVB and ECB values were approximately 2.84 eV and -1.035 eV (vs. NHE), respectively” and presented Scheme 1 as below. However, the position of VB is not at 2.84 eV in Scheme 1. If EVB is 2.84 eV and ECB is -1.035 eV as written, then the band gap will be 2.84+1.035=3.875 eV for BiOBr. However, authors claimed that the band gap of BiOBr is 2.84 eV.

 

Authors wrote “while the remaining h+ in the valence band undergoes a redox reaction with RhB to produce CO2 and H2O.” It is understood that HO• (hydroxyl radical) does not produce at VB. If this is the case, why EPR in Fig.9(b) revealed signal of hydroxyl radical?

If EPR in Fig.9(b) revealed the production of hydroxyl radical, why in Fig. 9(d) the scavenger of IPA did not show a sign of scavenging  hydroxyl radical that would certainly lead to the reduction of degradation percentage as reported in other literatures?

 

Authors are required to show the experimental error for each degradation efficiency. For example: 94%±??

 

Fig.3 Please add in the measurement of the thickness in the cross section images.

Fig.4 Authors are required to discuss the FTIR peaks for BiOBr, BiOCl and BiOI

Fig.6(b) What is R2 for each curve? And R2 for Fig.7(b)

In the experimental section, gram is used. But in Fig.7(a), molar is used. How did authors prepare it? Please detail the procedure?

Comments on the Quality of English Language

Minor editing of English language required

Author Response

Thank you very much for taking thetime to review this manuscript. Please find the detailed responses below and the corresponding revisions highlighted in the re-submitted files.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript can be published in present form.