Ni-Doped La_0.6Sr_0.4CoO₃ Perovskite as an Efficient Electrocatalyst for Oxygen Reduction and Evolution Reactions in Alkaline Media

Round 1

Reviewer 1 Report

The manuscript describes (Ni-doped La0.6Sr0.4CoO3 perovskite as an efficient electrocatalyst for oxygen reduction and evolution reaction in alkaline media)). The overall manuscript is clear, but there are some ambiguous parts. So, I asked for a revision.

1)    Please improve English writing and punctuation. For example:

Their electrode in line 12 must turn to the electrode.

Cathode in line 9 turns to cathodic.

pH 8 tern to pH 8.00, and etc.

2)    The first line of the abstract is too specific. It means that perovskites are used just in ZAB. Please rewrite it.

3)    It is better to mention more about the necessity for perovskites' fabrication in the abstract.

4)    Please write the aim of using Vulcan-XC73 and Nafion in the manuscript.

5)    Why concentration of O22-/O species is reduced as the amount of Nix (x=0.5, 0.8) is increased? (Concerning to XPS analysis)

6)    OER analysis can be done in both acidic and alkali media. Did you ever test the fabrication electrode in an acidic medium? If not, please do it and report the results.

7)      Ni-doped La0.6Sr0.4CoO3 perovskite has been synthesized before with the almost same method and different materials (DOI 10.1007/s11581-015-1606-9). Please mention your reasons that what are the advantages of using these materials in this manuscript.

The English language of this manuscript needs to be improved.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

This work provides an experimental study of Ni-doped La_0.6Sr_0.4CoO₃ perovskite catalysts for Zn-air batteries. By varying Ni content, the catalysts were synthesized by using combustion method. The La_0.6Sr_0.4Co_0.8Ni_0.2O₃ was found to be a potential catalyst candidate for oxygen reduction and evolution reactions. This investigation presents a potential structural engineering approach to tailor the performance of LSC for ZAB. The manuscript can be published in Catalysts after addressing the following issues:

1.      In Line 189, it is stated that “The spectra are displayed in Fig. 5”. However, Figure 5 showcases the LSV curves, not the XPS spectra. Similar issues are observed in Lines 201 (Fig 3c and 3d) and 209 (Fig. 3d).

2.      X-ray absorption spectroscopy is needed to characterize the oxidization state and surface electronic structures of La_0.6Sr_0.4Co_1-xNi_xO₃, in addition to XPS.

3.      The OER and ORR stability of LSCN-0.2 should be tested to assess its e long-term durability.

4.      How about the cycling performance of the ZAB at a higher current density, such as 50 mA cm^-2?

5.      The manuscript needs further refinement to prevent typographical errors, such as line 218 (nicle) and line 236 (Ej10).

There are some typos that should be corrected.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf