DFT Study of CO₂ Reduction Reaction to CH₃OH on Low-Index Cu Surfaces

Round 1

Reviewer 1 Report

It is a standard work of using DFT to study the reduction of CO2 to CH3OH on Cu surfaces with low-index orientation. Several suggestions/comments are provided below:

1. in equation 4, why is energy divided by 2A instead of A?

2. the geometries with adsorbate are only provided with a side view. Please consider rotating the view angle to include top-view-related information or add top-view geometries, otherwise, it's not clear how adsorbate is bonded to the surface from the current side view.

3. Please provide Gibbs free energy correction terms such as ZPE, TS, etc in the SI.

4. In the conclusion session, the authors claimed that Cu(110) can be a promising catalyst for the efficient and selective reduction of CO2RR to CH3OH. Based on figure 3, the adsorbed CO prefers to desorb compared to further hydrogenation. It seems like CO would be the selective product instead of CH3OH. What's the authors' comment?

Author Response

Please find the reply in the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors studied the surface effect on the selectivity and activity of three low index Cu surfaces for CO₂RR to methanol via CO₂ → *COOH → *CO→ *CHO → *CH₂O→ *CH₂OH → CH₃OH pathway. They found that the Cu (110) performs the best activity and the reduction reaction of CO₂ to *COOH is the potential-determining step. Their studies can help experimental scientists to design new catalysts for CO₂RR. This manuscript might be published in catalysts after a minor revision.

 A few comments are listed:

 (1) The manuscript writing could be further polished. For example, “potential-determing” should be “potential-determining"; “RDS” in the conclusion should be “PDS”.

 (2) It is better to list some references to support the authors’ idea. For example, the stability of various low index copper surfaces should be checked again, since the Cu(111) facet is usually considered as the most stable surface because the copper atoms own the largest Cu-Cu coordinated numbers.

 (3) Why don’t you consider the *HCOO intermediate in your reaction path?

 

Author Response

Please find the reply in the attachment

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Thanks authors for addressing my previous comments.