Stencil-Printed Scalable Radial Thermoelectric Device Using Sustainable Manufacturing Methods

Round 1

Reviewer 1 Report

The proposed study shows a low energy fabrication of printed thermoelectric devices. It provides interesting results and demonstrates potential applicability of the developed devices in waste heat energy harvesting. However, the proposed work needs some explanations and improvements:

(1) the paper is focused mainly on description of the experimental method and presentation of the prototype fabrication, but it lacks precisely stated objectives as well as description of the preliminary assumptions and hypotheses;

(2) the description and analysis of the state-of the art should be more comprehensively presented;

(3) the main innovation behind the presented work has to be clearly indicated and substantiated;

(4) the visibility of the Figure 5 (in particular the middle one) should be improved;

(5) the presentation of all graphs and equations should have a uniform pattern.

N/A

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

This paper proposes a novel method for manufacturing radial TEG device, which has larger power density than previous works of authors. However, this article has many problems as below:

1. The method of film fabrication is same as citation [36], and authors should explain the innovation and uniqueness of the sample preparation method in this paper.

2. The frequency of citation 36-39 in this paper is too high (more than 20 times), and many of them seems redundant (like citation [36-39] in 3.1, citation [36-39] after Figure 3 in 3.2, citation [39] after “The electrical conductivity depends on charge carrier concentration and carrier mobility” in 3.2, and so on). Some of them are cited to compared with previous works of authors, which is meaningless unless compared experimental results with other scholars (like citation [37-39] after “The average electrical conductivity (200 S/cm) of n-type chitosan-BTS composite films is also lower than bulk BTS (700-800 S/cm)”, and so on). Some authors of cited articles corresponding to citation [36-39] are authors of this paper, and these citations should be removed if authors cannot give suitable reasons for citing these articles.

3. Although authors of citation [36] is same as this paper, the figure of equipment of the radial device testing (Figure 1(b)) is almost identical to the Figure 3(b) in citation [36]. This problem may not be able to find if the difference in the color and position of the boxes is inexistence.

4. Moreover, other figures seem like figures in citation [36-38], authors should explain difference between these figures. The content of Figure 3 in this paper is same as Fig. 4 in citation [36]. The data in Figure 3(a) seems like the data in Fig. 4 in citation [36] multiplied by 10, and the data in Figure 3(b)~ (c) seem like the data in Fig. 4(b)~ (c) in citation [36]. The Figure 4(b) in this paper is same as Fig. 5 in citation [37], and Figure 4(d)~ (e) in this paper is partial intercepted from Fig. 6(a) and Fig6(d) in citation [38]. The data in Figure 5 seems likely to Fig. 7 in citation [38].

5. The contents in Table 1 are very confusing, like something done in a hurry before going to dinner. The word "ohm" in the third column of eighth row in Table 1 seems needless. The Max Power in the fourth column of sixth row in Table 1 is 310000, and authors should explain the reason of the large value. The font size in Table 1 is different, and the font size should be kept same.

Just judging by the repetition rate of the pictures, this paper should not be approved to be published in this journal unless this article is original and innovative after editing.

Editor or authors can find these repeat figures in partial references of this paper is list as below.

[36] Jang E, Banerjee P, Huang J, Madan D. High performance scalable and cost-effective thermoelectric devices fabricated using energy efficient methods and naturally occurring materials. Applied Energy, 2021, 294:117006.

[37] Banerjee P, Jang E, Huang J, Holley R, Vadnala S, Sheikh A, Trivedi A, Jackson K, Homman V K, Madan D. Thermoelectric performance enhancement of n-type chitosan-Bi2Te2.7Se0.3 composite films using heterogeneous grains and mechanical pressure. Journal of Electronic Materials, 2021, 50:2840-2851.

[38] Banerjee P, Huang J, Ambade R B, Jang E, Saeidi-Javash M, Zhang Y, Madan D. Effect of particle-size distribution and pressure-induced densification on the microstructure and properties of printable thermoelectric composites and high energy density flexible devices. Nano Energy, 2021, 89(B):106482.

Comments for author File: Comments.pdf

Author Response

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Reviewer 3 Report

1. The authors write Commercially available 100 mesh (a combination of micro- and nano-meter-sized TE particles) n-type BTS and p-type BST TE powders were used to fabricate and characterize TE films. However, this statement is not confirmed experimentally. An electron microscopic image of the original powders would have enriched the article.

2. The authors did not note the reflection at 2θ≈18о on the X-ray diffraction pattern, corresponding to the (006) plane

3. The color notation used is quite difficult to read in Figure 5b.

4. The authors constructed the so-called current-voltage characteristic of the resulting source and the resulting values of the output power versus the current value. The magnitude of the source current is determined by the sum of the internal resistance of the source and the resistance of the consumer. Therefore, the given formula (2) is erroneous. Depending on the resistance of the sensor, the power output can vary greatly. Therefore, when describing formula (2), it should be noted that this is the maximum possible power that can be obtained if RTEG and sensor resistance are equal.

Author Response

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Round 2

Reviewer 1 Report

The introduced amendments and extensions in the revised version of the article sufficiently improve the merits and overall style as well as scientific soundness of the paper.

The modifications and extras in the revised version of the article are appropriate. They complement well the work and it is now of sufficient quality level to be published.

Author Response

Thank you for liking our revised version

Reviewer 2 Report

According to the modified edition version of this paper, the authors have paid much attention to editing this work. However, I thought there were still many problems that needed to be addressed from the edition version and response to the reviewer’s comments.

1. The difference between the Figure 1 in the peer review-v3 and the Figure 1 in the peer review-v2 is the change of the font type. I don't think this diagram should contain any diagrams that are in other published papers and are not cited. Authors can use schematic diagrams to present the test equipment where outside white boxes like Variable resistors, Multimeter, and so on.

2. The response to question 4 seems unconvincing. According to your response from Q4 - the main difference is usually in the TE materials or composites type, processing methods, and results obtained, and these differences may cause different microstructures. In my opinion, authors should replace Figure 4 with a new SEM diagram of the BTS as n-type material and BST as p-type TE composites and fabricated radial TEG devices, or delete Figure 4.  

3. From the response to Q5, the reason for the unusual Max Power 310000μW (fourth column of sixth row) cannot be seen in your response, and this data cannot be found from ref [24]. The sample seems like 2D TEG according to dimensions of the fourth column, authors should describe the shape of this sample exactly.

4. Authors describe the printable strategy in this work as a low-energy input curing process and cost-effective, but the manufacturing process in this work from response to Q1 in the reviewer and manuscript seems like the energy consumption of this work is not in accord with the narration in the above context. Authors should explain with other manufacturing processes to explain why this method is a low-energy input curing process and cost-effective.

Author Response

Response to Reviewer’s Comments

Reviewer#2: According to the modified edition version of this paper, the authors have paid much attention to editing this work. However, I thought there were still many problems that needed to be addressed from the edition version and response to the reviewer’s comments.

Q1. The difference between the Figure 1 in the peer review-v3 and the Figure 1 in the peer review-v2 is the change of the font type. I don't think this diagram should contain any diagrams that are in other published papers and are not cited. Authors can use schematic diagrams to present the test equipment where outside white boxes like Variable resistors, Multimeter, and so on.

Response: Thank you for your suggestion. We have removed test setup (Figure 1b) from the manuscript.

Q2. The response to question 4 seems unconvincing. According to your response from Q4 - the main difference is usually in the TE materials or composites type, processing methods, and results obtained, and these differences may cause different microstructures. In my opinion, authors should replace Figure 4 with a new SEM diagram of the BTS as n-type material and BST as p-type TE composites and fabricated radial TEG devices, or delete Figure 4.

Response: Thank you for your suggestion. We have removed Figure4 from the manuscript as per your suggestion.  

Q3. From the response to Q5, the reason for the unusual Max Power 310000μW (fourth column of sixth row) cannot be seen in your response, and this data cannot be found from ref [24]. The sample seems like 2D TEG according to dimensions of the fourth column, authors should describe the shape of this sample exactly.

Response: Thank you for your suggestion. Sorry for showing max power 31000 μW power output reference in the table1. We have removed this row and column from the table.

Q4. Authors describe the printable strategy in this work as a low-energy input curing process and cost-effective, but the manufacturing process in this work from response to Q1 in the reviewer and manuscript seems like the energy consumption of this work is not in accord with the narration in the above context. Authors should explain with other manufacturing processes to explain why this method is a low-energy input curing process and cost-effective.

Response: Various additive manufacturing (printing) methods have recently been employed to manufacture thermoelectric generators (TEG) devices. These printing techniques consume excessive energy by using long-duration and high-temperature sintering to reduce the interfacial connections and grain boundaries between thermoelectric particles and improve electrical conductivity. This work aims to eliminate the high temperature and long-duration sintering process used in other additive manufacturing techniques therefore we call our process as low-energy input curing process.

Author Response File: Author Response.docx