Pt2 Dimer Anchored Vertically in Defective BN Monolayer as an Efficient Catalyst for N2 Reduction: A DFT Study
Round 1
Reviewer 1 Report
In this report authors present a DFT study on double atom catalysts with reversed sand which structures of metal dimers anchored in defective boron nitride monolayer for nitrogen reduction reactions.
This report is suitable for publication in this 'Catalyts' journal. However, I suggest authors to consider revising the article title. As the work presented in this study is wholly based on DFT study, it is appropriate if the title reflects the same.
On the lines of existing similar catalysts ( structures) that have been studied for nitrogen reduction reactions( NRR), authors chose another possible (interesting) topology to anchor transition metal atoms into defective BN layers. Nevertheless it is not yet clear whether it is feasible to synthesize and study such kind of electrocatalysts in practice.
This study might help other researchers consider a variety of different types of topologies in thier catalysts for NRR studies.
References and conclusions are in accordance with the study provided in the manuscript.
Though authors studied very few metal atoms in their study to make vn and vb type structures, they did not provide details on which type of anchoring ('vn' vs 'vb') is more effective for NRR studies and why? Authors also did not provide insights into the factors that can increase NRR and decrease HER activity in their structures. Discussions on these details might help researchers further focus on these type of structures with a variety of other metals.
Authors also did not discuss type of orbitals or bonding modes (for example; pi, sigma; bonding, anti bonding) that are involved in these structures in their pDOS studies. Perhaps addressing these issues might help why Pt is more effective than other metals in this study. Also it would be interesting to see whether size of atom plays an important role along with other electronic properties in these structures.
Over all in this study authors seems to be focused more on presenting their computational observations and less on evaluation of the observations.
Perhaps that's how computational study works!
some more comments
Page7 line 248: 'seise'? do you mean seize?
Page 8 line 257: sentence ' which might count for the electrocatalytic activity of these four DACs' is vague please modify.
Author Response
Thank you for the reviewer reports on our manuscript submitted to Catalysts (Manuscript Number: catalysts-1999841).
We are sending you a revised version. All suggestions and comments of the three Referees were carefully considered, and the manuscript has been modified accordingly.
To save the Referees’ time, all the changes in the manuscript are highlighted in red in the marked version, and our point-by-point responses are given in the Response letter in blue.
Reviewer 2 Report
Yu and co-authors studied theoretically the catalytic activity of different double atom catalyst (DACs) towards electrochemical conversion of nitrogen to ammonia. The obtained results indicate that DACs show better activity for the N2 reduction compared to the corresponding single atom catalysts. Among all modeled systems, Pt2 dimer vertically embedded in B vacancy in the BN monolayer shows the lowest limiting potential of -0.06 V and thus stands out as the most promising material.
I have the following question to the authors. Is there a particular reason why Pd2 dimers were not considered? I recommend adding in the manuscript a brief comment on this issue.
Additionally, but not mandatory, in the supplementary information could be added data about the metal-metal distance in the different metal dimers.
Minor notes:
Page 6, line 230 and page 9, line 314 “electrcatalysts” should be “electrocatalysts”
Author Response
Thank you for the reviewer reports on our manuscript submitted to Catalysts (Manuscript Number: catalysts-1999841).
We are sending you a revised version. All suggestions and comments of the three Referees were carefully considered, and the manuscript has been modified accordingly.
To save the Referees’ time, all the changes in the manuscript are highlighted in red in the marked version, and our point-by-point responses are given in the Response letter in blue.
Author Response File: 
Author Response.pdf
Reviewer 3 Report
This is a computational paper investigating the dimeric metal species. Paper is well written, and I did not find any shortcoming in calculations presented.
Authors do not comment whether hypothetical centers they have computed can ever be experimentally realized. Are there any hints on possible synthetic procedures which can result in such extremely undersaturated metal dimers?
Author Response
Thank you for the reviewer reports on our manuscript submitted to Catalysts (Manuscript Number: catalysts-1999841).
We are sending you a revised version. All suggestions and comments of the three Referees were carefully considered, and the manuscript has been modified accordingly.
To save the Referees’ time, all the changes in the manuscript are highlighted in red in the marked version, and our point-by-point responses are given in the Response letter in blue.
Author Response File: Author Response.pdf
