A CoFe₂O₄/Nb₂C-MXene-Modified Anode Improved the Performance Characteristics of a Microbial Fuel Cell in Terms of Bioelectricity Generation and Water Treatment

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In the present work, Ashraf et al. investigated the role of anode properties in microbial fuel cells to manage both wastewater treatment and energy production. The manuscript fits with the scope of the journal, presents a good level of material characterization and correlates the properties of the anode to the obtained performance. Overall, it can be published after that the following points will be addressed

·       Typos and grammar mistakes throughout the manuscript need to be carefully fixed in the revised version

·       The introduction needs to be significantly improved. The authors must pay attention to provide the necessary background to the reader in the cited field, following a typical funnel structure, referring to works which previously looked at the general issue of wastewater valorization (see for example 10.1016/j.cattod.2021.06.002), the importance of MFC (see for example 10.3390/w15020316) and then the role of optimization of the anode (see for example 10.1016/j.chemosphere.2020.128800)

·       Also in the introduction, the novelty of the work with respect to the literature should be clarified. And to do so, linked to the previous comment, a brief summary of the state of the art is necessary

·       In the methodology, a section related to the materials should be added (specifying if and where they were purchased)

·       The figures should be referred as “figure x” and not “figure x.y”; the quality of figure 2, 7 and 8 should be improved

·       In the paragraph 2.1.1, the amount of the materials, or concentration, should be added to permit the reproducibility of the experiment (as done in paragraph 2.1.2)

·       In the methodology, the procedure and instruments used for the characterization of the materials should be added; also the instrument used for COD analysis should be descripted

·       With regards to the experimental test, were they carried out in duplicate? What is the reproducibility?

·       The discussion on the comparison with previous studies could be improved by using a table where the key performance indicators, together with the reaction conditions, are reported

Comments on the Quality of English Language

Moderate editing of English language required.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Ashraf et al. report the impact of modified microbial fuel cell (MFC) anodes, including CoFe2O4@CF, Nb2C-MXene@CF, and CoFe2O4/Nb2C-21 MXene@CF. Various standard characterization tools were applied to support their findings. This study was written informatively to address electricity generation and water treatment. Therefore, this manuscript should be accepted after minor revisions, as summarized below.

 1. It is more informative to explain the MXene material's properties and MFC applications using relevant references.

2. A mismatch between the descriptions of figures in the main text and figures should be double-checked.

3. A careful revision of the hydrothermal synthesis process of cobalt ferrite nanocomposites is suggested using relevant references, such as a specific ratio for the amounts of cobalt and iron precursors.

4. It is suggested that the filter mesh size in the vacuum filtration should be provided.

5. A detailed description of why the CF anode was chosen to coat evenly rather than other materials

6. Typos should be carefully corrected (e.g., Lines 59, 93, and 256).

Author Response

Please see attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors replied to all the comments and improved the quality of the manuscript, which can be now accepted. 

My minor comment is checking the bibliography, which apparently is cut in the pdf version of the file