Slot-Die Process of a Sol–Gel Photocatalytic Porous Coating for Large-Area Fabrication of Functional Architectural Glass

Round 1

Reviewer 1 Report

There are some comments toward the manuscript.

1. The optical bandgap values of all formulations have been stressed in the abstract. It is suggested to shown the plots of transmittance vs. wavelength and the plots of (αhυ) vs. hν.
2. What’s the reason make the increase of optical bandgap with the presence of surfactant.
3. Please make sure that whether the "Figures 4a 4b 4c" (as shown in line 181 of the manuscript)  should revise as "Figures 4a 4c 4e" or not.

Author Response

Thank you for reviewing the article.
Some parts were rewritten to improve grammar and vocabulary as requested by the editor and other reviewers. Those changes have not been marked with track changes.
Responding to your revisions:
1) The graph for the calculation of the band gap using Tauc's formula is included, as well as an explanation of how it was performed. (page 6, lines 180-186)
2) The reason for the increase of the band gap in the presence of surfactants was explained as well as several bibliographic references. (page 7, lines 192-196)
3) The error in the numbering of the figures was corrected. Due to changes in the main text, the figures had to be renamed. (page 9)

Reviewer 2 Report

he authors described slot-die coating process as an alternative to the dip coating method to prepare functional photocatalytic coating. The topic could be interesting but the presentation of the work is very poor. Extensive English language review is another issue. The authors must include the following points

#1. There should be a clear schematic diagram of the coating process with detailed parameters explained.

#2. 3.3 and 3.3 subheadings are same

#3. Page 11, “The sols 286 were found to be stable at greater aging times, while shorter aging times provided coating 287 with smaller but increasing photocatalytic activity”, what does it mean?

#4. There are many language related error like “To shelter from outside lighting”, 

#5. Some images related to the cross-cut test should be presented for both coating process for comparison

#6. Authors didn’t include the adsorption effect on dye degradation test that must be included, since surface area play the key role.

#7. Authors compared their method with the dip coating one, but didn’t provide any data on the surface microstructure (SEM images), roughness and coating thicknesses, which are very important factors that controls the photocatalytic efficiency. These must be included and compared.

Author Response

Thank you for reviewing the article.
Some parts were rewritten to improve grammar and vocabulary as requested by the editor and other reviewers. Those changes have not been marked with track changes.
Responding to your revisions:
1) A diagram of the process with the variables was included. (page 15)
2) The title was corrected. (page 14)
3) The title was rewritten to improve the explanation. (page 14, lines 329-334)
4) As mentioned at the beginning, language errors were corrected or rewritten. (page 15, lines 382-386)
5) Cross-cut test images were added for both processes. (pages 8 & 14)
6) It was mentioned in several parts of the main text that there was no adsorption. We felt that it was not necessary to provide images of this process and we felt that it was sufficient to record it in the text. (page 9 lines 217-220, page 15 lines 387-391) 
7) Results of roughness, thickness and SEM characterizations as well as images were added. They were commented and compared in several parts of the main text. (page 5 lines 137-145, page 7 lines 197-203, page 12 lines 289-300)

Reviewer 3 Report

Please see attachment

Comments for author File: Comments.pdf

Author Response

Thank you for reviewing the article.
Some parts were rewritten to improve grammar and vocabulary as requested by the editor and other reviewers. Those changes have not been marked with track changes.
Responding to your revisions:
1) Further techniques to characterize the materials are included throughout the main text. (page 4 lines 129-136)
2) Same as point 1, they were included throughout the main text. (page 5 lines 137-145, page 7 lines 197-203)
3) The graph for the calculation of the band gap using Tauc's formula is included, as well as an explanation of how it was performed. (page 6, lines 180-186)
4) The text was rewritten for clarity and images were added. Provided data on characterization techniques. (page 12 lines 289-300, page 14 lines 348-352)
5) The errors suggested by the reviewer were corrected and, as mentioned at the beginning, the grammar and vocabulary of the entire text were revised. 

Round 2

Reviewer 3 Report

I accept the manuscript for publication in Catalysts.