Solvatochromism and Selective Sorption of Volatile Organic Solvents in Pyridylbenzoate Metal-Organic Frameworks

Round 1

Reviewer 1 Report

This manuscript presents three-dimensional isomorphous and isostructural MOFs from cobalt(II) and zinc(II) with two related ligands, 3-(4-pyridylbenzoate) (34pba) and 4-(4-pyridylbenzoate) (44pba). The sorption capacity for amines and chlorinated solvents of 1d and 3d was investigated, having selectivity to take up guest molecules and undergo colour changes depending on the chemical and physical properties of the guest molecules. These results give good examples to investigate and prepare the MOFs for sensing and separation applications. With a serious-minded viewing, I think that the results are interesting and this manuscript can be accepted to publish in Chemistry with a minor revision as the following questions are well replied.

(1) The authors used topology to elucidate the structure of compounds, but the analyzing software is absent. The authors should supply and cite it.

(2) The English language and style should be carefully checked.

Author Response

(1) We have added the reference to the paper in which the topology was established.

(2) We have read the paper and made corrections as needed.

Reviewer 2 Report

The manuscript entitled ‘Solvatochromism and selective sorption of volatile organic solvents in pyridylbenzoate metal-organic frameworks’ is well-written, interesting, has novelty and contains insightful applications for MOFs.

I recommend acceptance after very minor changes/corrections as highlighted below;

Abstract (line 9-10): Please add ‘the crystallization of’ or ‘to crystallize or ‘to form ’ such that the statement could perhaps reads as follows “Using cobalt(II) as a metal centre with different solvent systems afforded  the crystallization of isomorphous metal-organic frameworks {[Co(34pba)(44pba)]·DMF}n (1) and {[Co(34pba)(44pba)]·(C3H6O)}n (2) from mixed 4-(4-pyridyl)benzoate (44pba) and 3-(4-pyridyl)benzoate (34pba) ligands.

Abstract (line 19-20): Please rewrite this statement “Some sorption products were amorphous but the crystalline framework could be recovered on desorption.” so as to bring out more clarity that it was some of the resulting sorbents (after impregnation with VOCs) that became amorphous.

Materials and Methods (Line 71-81): Even though the information is presented in the discussion section, It would add more value (and make it more reader friendly) if the specific VOCs are mentioned in the 'Materials and Methods' section. Please also include details for regeneration of the MOFs i.e. temperature and time.

Author Response

We thank the reviewer for these helpful suggestions, which improve the clarity of the paper.  We have made all the changes suggested.  These are indicated using "track changes" in the revised manuscript.

Reviewer 3 Report

The manuscript by Ndamyabera et al. is dealing with a topic of interest within MOFs fields. It is well-presented and of broad interest for potential readers of the journal. I consider the manuscript suitable for publication. I just would like to recommend to check some mistakes in references 30 and 44. Also, I consider authors could make an extra effort on the references section, updating a little bit them.

Author Response

We thank the reviewer for pointing out the errors in the reference citations.  These have been corrected and are indicated using "track changes" in the revised manuscript.