Thermochromic Smart Windows Assisted by Photothermal Nanomaterials

Round 1

Reviewer 1 Report

The paper reviews thermochromic window using photothermal nanomaterials. However, this paper has many points to be improved. Please address the following comments.

 

1.         The introduction is too short. Readers cannot understand why review is necessary for this field. Please explain more about the value, strategy, contribution of this review.

2.         The number of the references are also too small. There are many papers related to this field. At least 100 references are required.

3.         Please improve the structure of the review paper. For example, the section 2 is entitled as “Types of thermochromic smart windows”. However, there are explanation of some materials. After that, “3 Common photothermal conversion materials” is placed.

4.         In the conclusion section, the authors give suggestion of (1) ~ (3). However, these are typical opinions. Please discuss deeper related to the mentioned references.

Author Response

Dear Editor and Referees:

 

Thanks for your letter and for the Referees’ comments concerning our manuscript entitled “Thermochromic Smart Windows Assisted by Photothermal Nanomaterials” (Manuscript ID: nanomaterials-1989252). We deeply appreciate the time and effort you’ve spent on reviewing our manuscript. These comments are really thoughtful and very helpful for revising and improving our paper, as well as the important guiding significance to our research. During the last days, we have referred to literatures, checked spelling and studied your comments carefully, and we have completed the modifications according to the referees’ comments.

 

The Referees’ comments and the responses to the comments are as follows:

 

Reviewer: 1#

The paper reviews thermochromic window using photothermal nanomaterials. However, this paper has many points to be improved. Please address the following comments.

Response:

We thank the Referee for the positive comments on our work. According to the Referee’s suggestion, we have supplemented the introduction, increased the number of references, and modified the conclusions. The modified part is highlighted.

 

Comment 1:

The introduction is too short. Readers cannot understand why review is necessary for this field. Please explain more about the value, strategy, contribution of this review.

Response:

Thanks for Referee’s kind suggestion. It is really true as the Referee suggested that the value, strategy, contribution of this review should be added. According to the Referee’s suggestion we have added this part in the revised manuscript. The modified is:

In recent years, with energy-saving and green development being vigorously promoted in recent years, smart windows have attracted much attention due to their outstanding energy-saving effect. The concept of "smart windows" was introduced by Granqvist in the 1980s[8]. It is an energy-saving window that regulates solar radiation by combining a dimming material[9-11] with a base material such as the glass. As an optical device, its core is the sensitive material attached to the glass. Under external excitation of light, electromagnetic radiation and temperature, the sensitive materials will color or fade thereby changing its own color and other optical properties, so that they can automatically adjust indoor temperature and light intensity according to the surrounding environment, and ultimately achieve the purpose of saving energy consumption.

At present, most typical smart windows require the external power supply or heating device to dynamically tune the optical properties of materials in response to external stimuli. However, these additional devices have significant disadvantages such as complex structure, low lifespan, and high energy consumption, which also greatly hinder their commercial utilization. In contrast, solar-driven thermochromic smart windows can adjust the optical properties actively through the strong absorption of solar energy by photothermal materials, achieving a dual response to light and temperature. The features of low cost, simple structure and low energy consumption are more conducive to the large-scale application in the future.

The smart window assisted by photothermal materials is extremely important for the development of smart windows. However, the systematical summary on this aspect is relatively rare. Therefore, in this review, several thermochromic smart windows with different substrates are presented, the auxiliary effect of different kinds of photothermal materials on the phase change of smart windows are reported, and finally the future research trends are prospected. This will provide references and suggestions for overcoming the problems of high response temperature and low response rate of traditional thermochromic smart windows.

 

Comment 2:

The number of the references are also too small. There are many papers related to this field. At least 100 references are required.

Response:

Thanks for Referee’s kind suggestion. According to the Referee’s suggestion, we have cited some literature published in recent years at appropriate locations, and the total number of references is 103.

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Comment 3:

Please improve the structure of the review paper. For example, the section 2 is entitled as “Types of thermochromic smart windows”. However, there are explanation of some materials. After that, “3 Common photothermal conversion materials” is placed.

Response:

Thanks for Referee’s kind suggestion. After careful consideration, according to the content of the paragraph, we changed the title of section 2 from “Type of thermochromic smart windows” to “Thermochromic Materials for smart windows”.

 

 

 

Comment 4:

In the conclusion section, the authors give suggestion of (1) ~ (3). However, these are typical opinions. Please discuss deeper related to the mentioned references.

Response:

Thanks for Referee’s kind suggestion. According to the Referee’s suggestion, we have discussed deeper related to the mentioned references. The modified is: “For example, in Table 1, the photothermal efficiency of Cu₇S₄ Nano Superlattice is significantly higher than that of Cu₇S₄ NPs[99].”, “As Au@Cu₇S₄ yolk-shell NPs[100], not only retain the respective absorption peaks of Au and Cu₇S₄ in UV-Vis-NIR spectra, but also show significantly enhanced absorption in the near-infrared region. And the photothermal conversion efficiency is also higher, which shows the total is greater than the sum of parts.”, “In addition to improving the conversion efficiency of photothermal materials, solar absorption efficiency is also an important parameter. In the field of solar cells, bionic anti-reflective periodic structures, such as butterfly wings and moth eyes, are often used on the surface of solar panels[103]. These rough nanostructures can effectively eliminate reflection and help them absorb more sunlight than smooth surfaces. Similarly, this structure is also applicable to smart windows, which will significantly shorten the response time.”

 

We tried our best to improve the manuscript and made some other changes in the manuscript. These changes will not influence the framework of the paper. And we have highlighted all the changes in the revised manuscript. We appreciate for Editor and Referees’ warm work earnestly, and hope that the correction will meet with approval.

Once again, thank you very much for your comments and suggestions!

Best wishes!

 

Yours Sincerely,

Haining Ji

 

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper is a nice and well written review which described several classes of promising photothermal materials. The content of the paper is appropriate and the choice of materials is correct. The language of the paper is fine. The figures are informative. Please, be sure that all of them are original or suitable agreements for reuse are achieved.

I suggest direct acceptance

Author Response

Dear Editor and Referees:

 

Thanks for your letter and for the Referees’ comments concerning our manuscript entitled “Thermochromic Smart Windows Assisted by Photothermal Nanomaterials” (Manuscript ID: nanomaterials-1989252). We deeply appreciate the time and effort you’ve spent on reviewing our manuscript. These comments are really thoughtful and very helpful for revising and improving our paper, as well as the important guiding significance to our research. During the last days, we have referred to literatures, checked spelling and studied your comments carefully, and we have completed the modifications according to the referees’ comments.

 

The Referees’ comments and the responses to the comments are as follows:

 

Reviewer: 2#

This paper is a nice and well written review which described several classes of promising photothermal materials. The content of the paper is appropriate and the choice of materials is correct. The language of the paper is fine. The figures are informative. Please, be sure that all of them are original or suitable agreements for reuse are achieved.

I suggest direct acceptance.

Response:

We thank the Referee for the positive comments on our work.

 

We tried our best to improve the manuscript and made some other changes in the manuscript. These changes will not influence the framework of the paper. And we have highlighted all the changes in the revised manuscript. We appreciate for Editor and Referees’ warm work earnestly, and hope that the correction will meet with approval.

Once again, thank you very much for your comments and suggestions!

Best wishes!

 

Yours Sincerely,

Haining Ji

 

Author Response File: Author Response.pdf

Reviewer 3 Report

This review article reports on the thermochromic smart windows that can regulate their optical properties actively in response to external temperature changes. To overcome the disadvantage of the conventional thermochromic smart windows that have generally problem with high response temperature and low response rate, photothermal nanomaterials that assist the phase transition of the thermochromic materials are investigated. From the overview of the current research, the outlooks and prospects for future research on the phase transition of photothermal materials assisted thermochromic smart windows are suggested in the Conclusions and perspective section. This article is well organized and provides a suggestion to overcome the problem of the conventional thermochromic smart windows with high response temperature and low response rate by improving the photothermal nanomaterials. This topic is suitable for this journal. The comments from this reviewer are as follows,

1.     The caption for Figure 1 should be added more information about (a) (b) (c).

2.     Page 7, line 125-128; “The GO dispersed in the PNIPAm hydrogels can make the originally transparent films reach the LCST at room temperature (30 ℃) and complete the phase change in a short time (Fig. 2b).” It is unclear how short time it changed from Fig. 2b. Please explain in more detail.

3.     Page 11, line 215; Figure 2a is not a proper citation here. Should this be Figure 3d? There is no mention about Figure 3 (a), (b), (d), and (e) in the main text. These figures should be cited in the main text at least once.

4.     Figure 4 (d), please indicate which are at 22°C and which are 36°C.

Author Response

Dear Editor and Referees:

 

Thanks for your letter and for the Referees’ comments concerning our manuscript entitled “Thermochromic Smart Windows Assisted by Photothermal Nanomaterials” (Manuscript ID: nanomaterials-1989252). We deeply appreciate the time and effort you’ve spent on reviewing our manuscript. These comments are really thoughtful and very helpful for revising and improving our paper, as well as the important guiding significance to our research. During the last days, we have referred to literatures, checked spelling and studied your comments carefully, and we have completed the modifications according to the referees’ comments.

 

The Referees’ comments and the responses to the comments are as follows:

 

Reviewer: 3#

This review article reports on the thermochromic smart windows that can regulate their optical properties actively in response to external temperature changes. To overcome the disadvantage of the conventional thermochromic smart windows that have generally problem with high response temperature and low response rate, photothermal nanomaterials that assist the phase transition of the thermochromic materials are investigated. From the overview of the current research, the outlooks and prospects for future research on the phase transition of photothermal materials assisted thermochromic smart windows are suggested in the Conclusions and perspective section. This article is well organized and provides a suggestion to overcome the problem of the conventional thermochromic smart windows with high response temperature and low response rate by improving the photothermal nanomaterials. This topic is suitable for this journal.

Response:

We thank the Referee for the positive comments on our work.

 

Comment 1:

The caption for Figure 1 should be added more information about (a) (b) (c).

Response:

Thanks for Referee’s kind suggestion. According to the Referee’s suggestion, we have added the information about Figure 1. The added description is: “(a) Metal insulator phase transition (MIT) of vanadium dioxide (VO₂).  (b) Liquid crystal changes transmittance by adjusting molecular orientation in response to temperature.  (c) Thermochromic hydrogels change transparency reversibly with temperature.”

 

Comment 2:

Page 7, line 125-128; “The GO dispersed in the PNIPAm hydrogels can make the originally transparent films reach the LCST at room temperature (30 ℃) and complete the phase change in a short time (Fig. 2b).” It is unclear how short time it changed from Fig. 2b. Please explain in more detail.

Response:

Thanks for Referee’s kind suggestion. According to the Referee’s suggestion, we have added a specific time for the film to arrive at LCST. The modified sentence is: “The GO dispersed in the PNIPAm hydrogels can make the originally transparent films reach the LCST at room temperature (30 ℃) and complete the phase change in 2 minutes (Fig. 2b).”

 

Comment 3:

Page 11, line 215; Figure 2a is not a proper citation here. Should this be Figure 3d? There is no mention about Figure 3 (a), (b), (d), and (e) in the main text. These figures should be cited in the main text at least once.

Response:

Thanks for Referee’s kind suggestion. We are very sorry for the incorrect citation. Figure 3 (a), (b), and (e) have been mentioned in the proper place of the text. The modified is: “Its steady-state temperature was close to 69 °C, however, the film without AuNRs only increased by 1 °C under the same conditions (Fig. 3a). And the switching temperature and colors of the film can be flexibly controlled by adjusting the concentration of AuNCs and the kind of thermochromic materials (Fig. 3b).” “When the temperature rises above LCST, the hydrogel structure shrinks and deforms, causing the AgNRs to stand up like flowers (Fig. 3d-e), and its IR emissivity got a slight increase from 0.947 to 0.958.”

 

Comment 4:

Figure 4 (d), please indicate which are at 22°C and which are 36°C.

Response:

Thanks for Referee’s kind suggestion. According to the referee's suggestion, we have indicated which temperature is 22 °C and which temperature is 36 °C in the description, and made marks on the figures. The modified is: “(d) Transparency changes of Cs_xWO₃/PAM-PNIPAM films with different PNIPAM concentrations at 22°C (above) and 36°C (below).”

Figure 4. (a) Schematic diagram of the chemical structure and working principle of the photochromic supramolecular hydrogel smart window.[73]  (b) Photographs of ATO composite hydrogel films with EGP5 content of 2, 5, and 8 mol%, respectively, before and after irradiation at 100 mW/cm² for 10 min.[73]  (c) Transmittance variation of Cs_xWO₃/PAM-PNIPAM film with temperature at 550 nm wavelength.[76]  (d) Transparency changes of Cs_xWO₃/PAM-PNIPAM films with different PNIPAM concentrations at 22°C (above) and 36°C (below).[76]

We tried our best to improve the manuscript and made some other changes in the manuscript. These changes will not influence the framework of the paper. And we have highlighted all the changes in the revised manuscript. We appreciate for Editor and Referees’ warm work earnestly, and hope that the correction will meet with approval.

Once again, thank you very much for your comments and suggestions!

Best wishes!

 

Yours Sincerely,

Haining Ji

 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors addreseed my comments well.