Nano-Bismuth-Sulfide for Advanced Optoelectronics
Round 1
Reviewer 1 Report
This review is needing an important effect in the Bi2S, which is spin-orbit effect and its impact on the electronic and optical properties. The section (2.1. Electrical band Structure and conduction properties), electrical should be electronic. Also this section needs a deep review on the electronic band structure and the debate of the electronic band gap. The 2nd missing is the NLO properties. Also authors should report on thermoelectric properties mainly in nanocomposite phase.
Author Response
This review is needing an important effect in the Bi2S, which is spin-orbit effect and its impact on the electronic and optical properties. The section (2.1. Electrical band Structure and conduction properties), electrical should be electronic. Also this section needs a deep review on the electronic band structure and the debate of the electronic band gap. The 2nd missing is the NLO properties. Also authors should report on thermoelectric properties mainly in nanocomposite phase.
R:We add more contents about the studies to the electronic band properties including the influences of the spin-orbit effect. These contents and related reference (H. Ben Abdallah and W. Ouerghui, "Spin–orbit coupling effect on electronic, linear and nonlinear optical properties of Bi2S3 and the ternary bismuth sulfide Bi2S2.75Se0.25: Ab-initio calculations," Optical and Quantum Electronics, vol. 54, p. 20, 2021) are added in the Section 3.1. On the other hand, we fully agree with the review’s comment about the missing discussion on NLO of Bi2S3, and these contents and related references (H. Ben Abdallah and W. Ouerghui, "Spin–orbit coupling effect on electronic, linear and nonlinear optical properties of Bi2S3 and the ternary bismuth sulfide Bi2S2.75Se0.25: Ab-initio calculations," Optical and Quantum Electronics, vol. 54, p. 20, 2021; X. Yang, W. Xiang, H. Zhao, X. Zhang, X. Liang, S. Dai, et al., "Third-order nonlinear optical properties of Bi2S3 nanocrystals doped in sodium borosilicate glass studied with Z-scan technique," Materials Research Bulletin, vol. 46, pp. 355-360, 2011) are added to Section 3.2. Besides, we enhances the discussion to thermoelectric reports in nanocomposite phase besides the bulk results presented in original draft (W. Liu, C. F. Guo, M. Yao, Y. Lan, H. Zhang, Q. Zhang, et al., "Bi2S3 nanonetwork as precursor for improved thermoelectric performance," Nano Energy, vol. 4, pp. 113-122, 2014).
Reviewer 2 Report
The authors reviewed the most recent works of nano-bismuth-sulfide for applications in optoelectronics. The paper is well organized, though they need to explain more in some important progresses.
In section 2.2, what kind of process was applied to modified the PL peak? The shift of peak was attributed to he crystal defects. Can it increase the non-radiative recombination?
In section 4.1, speed is important for photo-detector. One work Ref[92] that improved the response of photo detector should be explain more in detail. Like what they did to accelerate the carrier relaxation in such heterojunction?
Please keep the format clean especially in reference. There are lots of error for Bi2S3.
Author Response
The authors reviewed the most recent works of nano-bismuth-sulfide for applications in optoelectronics. The paper is well organized, though they need to explain more in some important progresses.
Q1: In section 2.2, what kind of process was applied to modified the PL peak? The shift of peak was attributed to the crystal defects. Can it increase the non-radiative recombination?
R1: the samples for PL studies is synthesized via a high power sonication process (N. Dhar, N. Syed, M. Mohiuddin, A. Jannat, A. Zavabeti, B. Y. Zhang, et al., "Exfoliation Behavior of van der Waals Strings: Case Study of Bi2S3," ACS Applied Materials & Interfaces, vol. 10, pp. 42603-42611, 2018) and the processing time (from 0.5h to 3.5h) control the modification of the PL peak. Although the shift of peak is ascribed to the crystal defects, we fully agree the viewpoint of the reviewer on the potential increase the non-radiative recombination. Some additional discussions on this point are added in Section 3.2 of revised draft.
Q2: In section 4.1, speed is important for photo-detector. One work Ref[92] that improved the response of photo detector should be explain more in detail. Like what they did to accelerate the carrier relaxation in such heterojunction?
R2: Yes, the speed is critical. Basically, it is suggested that the Bi2S3 and Bi2S3-xOx is respectively n-type and p-type, and the intrinsic electrical field of PN junction is well-known beneficial to accelerate carrier motion. Moreover, other than the junctions like Bi2S3/BiOX (X=Cl, I) (Q. Wang, Z. Liu, H. Feng, R. Jin, S. Zhang, and S. Gao, "Engineering Bi2S3/BiOI p-n heterojunction to sensitize TiO2 nanotube arrays photoelectrodes for highly efficient solar cells and photocatalysts," Ceramics International, vol. 45, pp. 3995-4002, 2019), Bi2S3/ Bi2S3-xOx system could be with better lattice matching, which reduce the interface defect. Such that, the Bi2S3/ Bi2S3-xOx could be heterojunction with good response speed.
Q3: Please keep the format clean especially in reference. There are lots of error for Bi2S3.
R3: We re-check the references format and revise the errors within.
Reviewer 3 Report
This manuscript is a review presenting the recent advances of growth of Bi2S3 nanostructures, electrical and optical properties of Bi2S3, and emerging optoelectronic applications. From the content of the manuscript, the manuscript describes the progress in these areas in detail. The following suggestions are given.
1. Since the manuscript is a review, it is necessary to add some of the author's own work in addition to the work of others.
2. English language and style are minor spell check required.
3. As a review, the manuscript's outlook for future research is not clear enough.
Author Response
This manuscript is a review presenting the recent advances of growth of Bi2S3 nanostructures, electrical and optical properties of Bi2S3, and emerging optoelectronic applications. From the content of the manuscript, the manuscript describes the progress in these areas in detail. The following suggestions are given.
Q1: Since the manuscript is a review, it is necessary to add some of the author's own work in addition to the work of others.
R1: There are some author's own works in this field, including Refs. 18,19,22,23,56,60,82,92. These work concerning the fabrication of nano-Bi2S3 and its MNR properties, trap-state probing, photondetection, memtistor, etc., and are discussed in this review.
Q2: English language and style are minor spell check required.
R2: We revise the content, and polish the English language. We wish it could be better.
Q3: As a review, the manuscript's outlook for future research is not clear enough.
R3: We revise the outlook parts of the contents. Especially considering that we add the more contents and discussions about the spin-orbit coupling, non-linear optics of Bi2S3, the corresponding outlook for future research on these aspects is added in this section. We wish these revision could present a more comprehensive outlook for the future of this field.
Reviewer 4 Report
The authors intended to provide a comprehensive review on the current progress of nano-bismuth-sulfide for optoelectronics. The electrical and optical properties, synthesis methods, as well as the applications in optoelectronic devices are discussed. The topic of this manuscript is interesting and attractive. However, major efforts are still needed to improve the organization and discussions of the review paper.
1. The organization of the manuscript should be improved to make it more readable. As a major topic, the definition of "nano-bismuth-sulfide" and the crystal structure of bismuth sulfide should be provided and discussed in the introduction section. In the properties section, it mentioned the properties of many nanostructured Bi2S3. As a result, it would be better to describe the synthesis methods of these nano-Bi2S3 first.
2. Many discussions in the manuscript are lack of logic. For example, in the Fabrication section, the different methods for the synthesis of Bi2S3 are not well classified. From Table 3 and 4, it is obvious that many different synthesis approaches have been developed. A proper classification of these methods and their comparison should be provided. In particular, detailed discussions about the products from these methods should be provided, rather than simply describe the synthesis process.
3. Many discussions and descriptions of the figures and tables are missed, which leads to many confusions.
4. There are many grammar mistakes throughout the manuscript. The authors should carefully check the language.
Author Response
The authors intended to provide a comprehensive review on the current progress of nano-bismuth-sulfide for optoelectronics. The electrical and optical properties, synthesis methods, as well as the applications in optoelectronic devices are discussed. The topic of this manuscript is interesting and attractive. However, major efforts are still needed to improve the organization and discussions of the review paper.
Q1: The organization of the manuscript should be improved to make it more readable. As a major topic, the definition of "nano-bismuth-sulfide" and the crystal structure of bismuth sulfide should be provided and discussed in the introduction section. In the properties section, it mentioned the properties of many nanostructured Bi2S3. As a result, it would be better to describe the synthesis methods of these nano-Bi2S3 first. Synthesis methods parts are put before the properties section.
R1: We define the "nano-bismuth-sulfide" and add the discussion to the crystal structure of bi2s3 in the introduction section. And we re-arrange the contents organization as
Q2: Many discussions in the manuscript are lack of logic. For example, in the Fabrication section, the different methods for the synthesis of Bi2S3 are not well classified. From Table 3 and 4, it is obvious that many different synthesis approaches have been developed. A proper classification of these methods and their comparison should be provided. In particular, detailed discussions about the products from these methods should be provided, rather than simply describe the synthesis process.
R2: We rearrange the discussions to the Fabrication section, and classify the different synthesis approaches based on the processing catalogue as two types: “Top-down” and “bottom-up”. We wish the revised fabrication section could be more logical-rational.
Q3: Many discussions and descriptions of the figures and tables are missed, which leads to many confusions.
R: we modify the figures and tables as well as the corresponding discussions, all the revised parts are red-marked. And we wish the revised contents could be less confused.
Q4: There are many grammar mistakes throughout the manuscript. The authors should carefully check the language.
R4: We revise the content, and polish the English language. We wish it could be better.
Round 2
Reviewer 1 Report
Authors have improved the review and listed enough references to encourage readers. The topic is of high importance and interest for the nanotechnology applications. I recommend it for publications
Reviewer 3 Report
The revised manuscript has been added with the required research content, meeting the reviewer's modification requirements.
Reviewer 4 Report
In the previous review report, a Major Revision was suggested. However, it seems that only slight changes are made and many issues are still existed. Many important discussions are still missing. As a result, I do not recommend the acceptance of the manuscript for publication.
