Effects of the Stacking Faults on the Electrical Resistance of Highly Ordered Graphite Bulk Samples

Round 1

Reviewer 1 Report

This article studies the electrical resistance of highly ordered and natural graphite bulk samples. The topic, quality and length of the work are suitable for C-Journal of Carbon Research journal. Although the article is well written and both the experimental and the results are correctly explained, some small improvements would be necessary before publication:

Abstract: some indication of the experimental measurement system used is missing (for instance: “four points method”.

Introduction: Because these are measurements of “bulk” materials, a discussion and references to values ​​reported in the literature for measured bulk graphite materials must be included. Anisotropy has been highlighted for graphite-based materials such as nanotubes or carbon nanofibers. Articles on bulk electrical conductivity (and resistance) of graphite-based carbon materials:

https://0-doi-org.brum.beds.ac.uk/10.1016/S0008-6223(02)00196-3

https://0-doi-org.brum.beds.ac.uk/10.1016/j.powtec.2018.09.038

Once the resistance is measured, why is the electrical conductivity of the materials not calculated?

Despite having a Discussion section, the article would need a clearer Conclusions section. The conclusions of the work and its novelty are not clear throughout the manuscript.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper investigates the electrical properties of highly oriented graphite samples near room temperature and insists that the interesting characteristics comes from the inner stacking fault in the samples. The exhibited data in this report is mainly the electrical properties, without the inner structural information. The expression in the title “Possible Pitfalls” is referred through other literature. The pitfalls are not confirmed in this report. Authors should focus on the electrical properties, and the possible mechanism is the additional information.

I think this paper should be refined.

Good point: interesting electrical characteristics

Bad point: the inner structural information by authors does not exist

I commented for the manuscript as follows.

LL41-43

“Because of the expected superconducting [7,12,15–17] and/or magnetic transitions [18], the temperature range above room temperature is of special interest.”

The temperature range of 300 K ≤ T ≤ 410 K is investigated in this study, but the reason why the authors selected this temperature range is not so clear.

I think authors should clarify the position of this report.

LL48-49

“Figure 1 shows a scanning electron microscope image taken directly at the edge of a bulk HOPG sample.”

Please insert the orientation information in Fig. 1

Ex.) c-axis

L107

“subte”

Is this “subtle” ?

LL218-222

“Assuming therefore that the origin for the observed changes in the resistance of bulk graphite is related to the diffusion of hydrogen (or water) molecules, this must happen within the stacking faults simply because no such effect is measured when the stacking faults or interfaces are away from the input current path. Whatever the detailed origin for the observed large changes in the resistance at high enough temperatures, our results indicate that the superconducting properties of the interfaces can vanish after annealing.”

I could not catch the intended meaning. Please clarify.

Overall

I think the section of conclusion or summary is necessary.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors effectively addressed all of the reviewer's comments. The article is ready for publication in this form.

Reviewer 2 Report

The commented points were revised. I think this report is suitable to publish.