Towards a Future Hydrogen Supply Chain: A Review of Technologies and Challenges
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsReview the Manuscript ID: sustainability-2802476
Title: Towards a Future Hydrogen Supply Chain: A Review of Technologies and Challenges
In this work the authors provided a systematic review of the technologies essential to the hydrogen supply chain, encompassing hydrogen production, storage, transportation, and utilization, followed by a discussion of the associated challenges and future prospects.
The topic covered in the article is interesting and current.
The article is well structured, with an adequate bibliographic review.
However, authors must improve the paper.
- Review the text and formatting of the document.
- The content of the paper needs to be academically inquisitive make a critical analysis of the research. Avoid neutral comments that only state what the cited work has reported but go beyond and identify research gaps, limitations, and opportunities for further research.
- Please sort the keywords alphabetically.
Comments on the Quality of English Language
Review the text and formatting of the document.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authors
In the article, the authors presented an overview of various elements related to the hydrogen supply chain, technologies of its production, storage, transport and utilization. The manuscript describes many complex hydrogen technologies, but is written in a simple and understandable language for the average reader who is not a specialist in the issues described. Moreover, the manuscript contains many interesting results and should be published after minor corrections. The authors should describe in more detail the latest results on various technologies for hydrogen production, storage, transport and utilization. For example, the "hydrogen storage" section should be based on newer publications that also appeared in Int. J. Hydrogen Energy. The typical metal hydrides listed in Table 4 have been known for a long time. However, the authors do not mention anything, for example, about magnesium-based nanocomposites or high-entropy alloys that reversibly absorb hydrogen.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThis review discusses the basic principles of photocatalytic hydrogen evolution and introduces the materials used in photocatalytic systems, including semiconductor photocatalysts such as TiO2, ZnO, organic photocatalysts, quantum dots, nanostructures and emerging materials. It is revealed that many strategies are involved in improving the photocatalytic activity of hydrogen, including band gap engineering, heterostructure construction, double co-catalyst utilization, vacancy method, high temperature photocatalytic water cracking, modulation and combination technology. The factors affecting photocatalytic hydrogen production are discussed, including the composition, morphology and structure of catalyst, reaction conditions and light source characteristics.
1. This review seems to simply introduce the mechanism, catalyst and influencing factors of photocatalytic hydrogen production, and there seems to be no special highlights.
2. In the introduction, the recently development about semiconductor photocatalysts should be summarized e.g., Materials Today Nano, 2022, 18, 100204; Green Energy & Environment, 2023, 8, 864-873.
3. In this review, the author introduces the work of many researchers, but it is basically written description, and it is suggested to add some sketches.
4. The authors give six key words, but it seems that many of them are repetitive and not enough to clearly define the content of this review.
5. The author has introduced many catalysts for photocatalytic hydrogen production. What are the advantages and disadvantages of each catalyst and which one is more suitable for photocatalytic hydrogen production?
6. Some minor mistakes including some grammar should be checked and corrected. The manuscript should be improved by an English spoken expert.
Comments on the Quality of English LanguageNone
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
