Designed Mesoporous Architecture by 10–100 nm TiO2 as Electron Transport Materials in Carbon-Based Multiporous-Layered-Electrode Perovskite Solar Cells
Vladimir Kochereshko
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsIn this manuscript, the authors investigated the effect of TiO2 particle size on the performance of perovskite solar cells. Sufficient characterizations have been conducted and demonstrated in a clear way. It is acceptable for publication on the journal of Photonics after addressing the following issue.
1. JV curves are suggested to be presented.
Author Response
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Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors have presented an interesting study on the fabrication and performance of fully printable carbon-based multi-porous-layered-electrode perovskite solar cells (MPLE-PSCs). They investigated the influence of particle diameter in the mesoporous TiO2 layer, which serves as the electron transport layer, on the properties and performance of MPLE-PSCs.
Overall, this study provides valuable insights into the relationship between particle diameter, porosity, and photovoltaic performance in MPLE-PSCs. The employed characterization techniques are appropriate and support the conclusions drawn.
I recommend this manuscript for publication after a minor revision.
However, there are a couple of points that need to be addressed:
Firstly, the authors should correct the reported value of the highest achieved power conversion efficiency for perovskite solar cells.
Secondly, the manuscript could benefit from improvements in English language usage, particularly in lines 52-55. It would be beneficial to revise these lines to enhance clarity and coherence.
Additionally, there are two specific questions that should be addressed:
1. Can the authors present the cross-sectional FE-SEM images of the 43 nm TiO2 nanoparticles-based device as well?
2. What about the stability of these devices?
Please consider these suggestions for the improvement of the manuscript. Once these minor revisions are made, I believe the study will be suitable for publication.
Comments on the Quality of English LanguageThe manuscript is well written, as it is clear, concise, and effectively communicates the research findings.
Author Response
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Reviewer 3 Report
Comments and Suggestions for AuthorsIn this manuscript, the authors designed a mesoporous architecture with 10-100 nm TiO2 nanoparticles as electron transport layer for carbon-based multi-porous-layered-electrode perovskite solar cells. They have achieved an optimal device performance by controlling the size of TiO2 nanoparticles. The fully printable carbon-based perovskite solar cells have attracted tremendous attention on account of its scalability, cost-effective and excellent device stability. Despite the reported device performance is not such efficient, the detailed device fabrication process and the optimized TiO2 nanoparticles is beneficial for the later device manufacture with higher performance for similar device architecture. Additionally, this technology is promising for the scalable production of perovskite solar cells and modules. Thus, this work has the potential to be published in Photonics.
However, more scientific details have to be firmly addressed, and I recommend the work to be accepted after a major revision by the following points.
1. To visually assess the device performance, I advise the authors exhibit the J-V curves (both at forward and reverse scan) of devices fabricated using TiO2 nanoparticles with various diameter.
2. In general, terpilenol is used for the fabrication of TiO2 pastes, and what do you think of its function for the paste quality?
3. What about the morphology and thickness of the carbon electrode used in this work?
4. To obtain the exact size of TiO2 nanoparticles, I advise the authors confirm their size with TEM, and compare the calculation with the TEM results.
5. How about the device operational stability? What about the relationship between the size of TiO2 nanoparticles and the device stability?
6. Please check and modify the reference style according to the Journal requirements.
Comments on the Quality of English LanguageThe quality of English language is good.
Author Response
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Reviewer 4 Report
Comments and Suggestions for AuthorsThe paper of Takaya Shioki, Ryuki Tsuji, Kota Oishi and Seigo Ito "Designed Mesoporous Architecture by Using 10-100 nm TiO2 Nanoparticles as Electron Transport Layer in Carbon-Based Multi-Porous-Layered-Electrode Perovskite Solar Cells" deals with the development of manufacturing and characterization of perovskite-based solar cells with porous electrodes. The article may be useful for engineers engaged in the development of a new generation of solar cells.
However, I have a number of comments. Firstly, the abstract should contain a summary of the main idea of the article. In this manuscript, however, the abstract is full of abbreviations and excessive specificity. As a result, it is impossible to understand the main idea of the article from the abstract. Second, sample preparation is described in excessive detail. Is it worthwhile to specify the diameter of the mortar in which the TiO2 powder was prepared in the article? Such details lose the main idea of the work.
Overall, it seems to me that although the article is useful, it is not well suited for Photonics Magazine. It is more suitable for a more specialized journal in chemistry or technology. I recommend to resubmit the paper to other journal concerned with chemistry or technology.
Author Response
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Reviewer 5 Report
Comments and Suggestions for AuthorsThe manuscript presents the function of the porous structure of the mesoporous TiO2 layer on the performance of solar cells in multi-porous-layered-electrode perovskite solar cells by using six kinds of TiO2 with different particle diameters and crystalline phases. The porosity of the mesoporous TiO2 layer as the electron transport layer in multi-porous-layered-electrode perovskite solar cells is controlled by varying the particle diameter of TiO2 nanoparticles, in the range 14 nm - 98 nm. The title is exciting and the results show good improvement in this area. I feel this manuscript can be accepted for publication pending some minor revisions:
(1) The topic is interesting but the title of the manuscript is a bit long and can be shortened.
(2) The mode field distribution of the carbon-based multi-porous-layered-electrode perovskite solar cell presented in Figure 1 can be useful for readers. It is recommended to add a figure for this reason.
(3) The authors present the absorbed photon-to-current conversion efficiency as Eq. (6. Please explain the use of this equation instead of quantum efficiency.
(4) It is suggested to compare the important results such as fill factor, efficiency, short circuit current, open circuit voltage, and so on by other recent researches.
(5) The literature survey is well written and the following references are recommended to address in the manuscript: 10.1149/10901.0011ecst; 10.1016/j.solener.2018.05.012; 10.3390/photonics7040133.
(6) The manuscript needs to be edited, for example in line 310: " ... different particle diameter and crystalline phases. ..."
(7) A list of all abbreviations at the end of the manuscript can be helpful for readers.
(8) The fabrication process, test conditions, and environmental effects should be described and addressed in more details.
(9) Please add scale bars for Figure 4.
Author Response
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Reviewer 6 Report
Comments and Suggestions for AuthorsIn this manuscript, the porosity of the 10 mesoporous TiO2 layer as the electron transport layer in MPLE-PSCs was controlled by varying the 11-particle diameter of TiO2 nanoparticles, from 14 nm to 98 nm. The results of IPCE, visible light reflectance spectroscopy, pore-size distribution, XRD, FE-SEM, and photovoltaic parameters of MPLE-PSCs are discussed. The results are interesting and may merit publication in Photonics. Before recommending publication, I would like to ask the authors to carefully address the following questions:
1) Does the size of TiO2 nanoparticles has any effect on the device stability? If has, how?
2) How about the wetting ability of different mesoporous TiO2 layers? Does this have any effects on the crystallization of the perovskite films?
Comments on the Quality of English LanguageNo
Author Response
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Round 2
Reviewer 3 Report
Comments and Suggestions for AuthorsI am satisfied with the author's reply, it can be accepted.
Reviewer 4 Report
Comments and Suggestions for AuthorsTakaya Shioki, Ryuki Tsuji, Kota Oishi, Naoki Fukumuro, and Seigo Ito's paper "Engineered mesoporous architecture based on 10-100 nm TiO2 as electron-transport material in carbon-based perovskite solar cells with multilayer electrode" is devoted to the development of fabrication technology for porous carbon-based perovskite solar cells using completely non-vacuum manufacturing processes. Undoubtedly, this work is very useful for improving solar cell manufacturing. However, I did not find any information related to optics or photonics per se in the paper.
There is one more remark on the article's layout. The specific parameters of TiO2 are given in the title: 10-100 nm. Does this mean that the results obtained are not valid for thicknesses of 9 nm or 101 nm?
I think the article is useful, but more suitable for some other MDPI journal. For example, for Solar, Applied Nano, Applied Science, etc.
