The Fabrication of Cu₂O-u/g-C₃N₄ Heterojunction and Its Application in CO₂ Photoreduction

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The Manuscript Numbered “Catalysts-3759141" and titled “The fabrication of Cu₂O-u/g-C₃N₄ heterojunction and its application in CO₂ photoreduction" focuses on the fabrication of Cu2O-u/g-C3N4 photocatalysts via a hydrothermal method. Under 175 W mercury lamp irradiation, it catalyzed liquid-phase CO2 photoreduction to formic acid, acetic acid, and methanol.

However, the manuscript suffers from some critical issues and can be considered for publication after correcting the typographical errors and major corrections.

 

Comments to the authors:

• The introduction section needs to be improved and include more references.
• The Keywords should be 5 or 6 words.
• How did the authors detect methanol?
• Please adjust the resolution of Fig.1 and Fig.6.
• Where is the high resolution of C1s, Cu2p, and O1s XPS peaks? Support the C1s and Cu2p discussion with references?
• Why was the total CO2 conversion in TEOA systems several times higher than in isopropanol? Support with references.
• Please compare your work with previously published papers in photocatalytic CO2 conversion, such as

10.1016/j.mssp.2024.109160 & 10.1016/j.jece.2023.110167

• Improve the discussion of the mechanism and support with references (section 3.3.4).

• The entire manuscript has many typos, formatting, and grammatical errors. Therefore, the authors should correct them carefully.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This paper reported, “The fabrication of Cu₂O-u/g-C₃N₄ heterojunction and its application in CO₂ photoreduction”. The author presents hetrojunction strategy in photoreduction which obtain C1 products. The manscript is organized well but there are few points which needs to be considered before publication.

The introduction section should discuss various kinds of CO2 conversion techniques then discuss why phototreduction is needed. For this purpose the [Carbon Capture Science & Technology, 15 (2025) 100405], this is effective to cite here. Could you write few sentences why Cu₂O-u/g-C₃N₄ used in the introduction section.

Please describe the preparation method in detail. You may present complete detail in supplementary document. Why chlorine precursors of salt is used. Is there any negative effects of chlorine?

Fig. 2a, there are many small peaks in the XRD pattern of Cu₂O-u/g-C₃N₄ sample. Could you please explain, what could be possibilities. Fig. 2b, it would be more clear if you present the XPS spectrum instead of XPS survey.

Fig. 3, It would be better if you present the TEM images with some explanation. What information we are getting from the current figures?

Fig. 11c, the reuseability lost after 3 cycles. It would be interesting if you add some characterization after 4 cycles.

There should be one comparison table to compare the performance of current work with the literature.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors addressed all the comments well.