Artificial Intelligence and Sustainability in Industry 4.0 and 5.0: Trends, Networks of Leading Countries and Evolution of the Research Focus

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript presents a systematic literature review on the intersection of AI, sustainability, circular economy, and Industry 4.0/5.0, with a specific emphasis on SDG 12. The authors searched Scopus and Web of Science from 2015 to 2025, yielding a dataset of 235 references.     The analysis is conducted in three phases: basic bibliometric trends, thematic classification across research focus, industrial concept, sector, AI type, and sustainability aspects, and VOSviewer-based mapping of country collaboration and keyword co-occurrence/temporal dynamics. Results suggest a strong managerial skew, dominance of Industry 4.0 over Industry 5.0, and comparatively limited explicit integration of the circular economy.
Drawbacks:
1. The core query centers on supply chain + AI, with unspecified variations for sustainable production and consumption. If the aim is to comprehensively connect AI, circular economy, Industry 4.0/5.0, and SDG 12 across industrial paradigms, the search string should likely also include explicit terms for circular economy, Industry 4.0, Industry 5.0, and SDG 12. The present approach may systematically under-sample non-supply-chain literatures relevant to Industry 5.0 human-centricity, socio-technical governance, or circular design outside SCM.
2. The paper references a selection process figure and three analysis phases, but the text does not show detailed inclusion and exclusion criteria, duplicate handling, or screening procedures. A systematic review claim would be stronger with PRISMA-aligned reporting and a concise table of criteria and reasons for exclusion.
3. The classification spans multiple dimensions. However, the operational definitions, coding rules, and whether multiple coders were used are not evident. This makes it harder to interpret claims like the managerial dominance or low Industry 5.0 share as a true field signal rather than a coding artifact.
4. Table 1 reports percentages across sub-variables for AI types and sustainability aspects. It is unclear whether studies can be counted in multiple categories, whether percentages represent shares of the whole corpus per tag, and whether any normalization was applied. Without this, the interpretability and comparability of the reported percentages are reduced.
5. Country mapping includes only countries with >5 papers. Keyword co-occurrence uses >10 occurrences. These are reasonable defaults, but the robustness of cluster structures to threshold shifts is not discussed. This is particularly important in an emerging, rapidly expanding topic area.
6. The manuscript interprets high average citations per document for smaller countries and lower averages for large producers. Without normalizing for publication year or field, these comparisons can be misleading, especially since older papers tend to accumulate more citations and topic subfields differ in their baseline citation density.
Recommendations:
1. Provide the exact final queries for all databases and consider adding explicit terms for circular economy, Industry 4.0 and 5.0, and SDG 12 to better align the dataset with the paper’s stated conceptual scope.
2. Add a PRISMA-style methods subsection, including detailed inclusion and exclusion criteria, screening steps, duplicate removal procedure, etc.
3. Specify whether categories are non-mutually exclusive and add n-values alongside percentages. This will prevent misinterpretation and facilitate reuse by other researchers.
4. Briefly test alternative thresholds and report whether cluster composition meaningfully changes. This will enhance confidence in the network interpretations.

Author Response

We would like to sincerely thank the reviewer for taking the time to carefully read our manuscript and for providing valuable comments and suggestions, which have helped improve the scientific quality, clarity, and overall readability of our work. Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors:

Thank you for submitting your work to Sustainability.
This topic is emerging in the current era.
Please find several recommendations to improve the quality of your manuscript:
1. Introduction: This study examines the contribution of AI, circular economy principles, and industrial paradigms to SDG 12. Yet, the authors have provided background information on AI, the circular economy, and Industry 5.0; however, there is no rationale for aligning their contribution with SDG 12. What is the main reason for selecting SDG 12 instead of others? This needs to be added in the background information about their intense relationship from previous research; thus, it is logical to discuss that specific goal. Further, a gap or controversy in the literature needs to be emphasized.
2. Materials and Methods: This section shows the step-by-step process the authors used to conduct the comprehensive systematic review. It is strongly encouraged to specify one method, e.g., the PRISMA method, to enhance the academic soundness of this study.
3. Results: Table 1 shows the overview of published studies by research variables. The rightmost column shows the percentage share of published studies. However, the total percentage is not 100%. The authors need to justify it. In addition, there is no sub-variable of the circular economy. Some examples of sub-variables of the circular economy include reduce, reuse, recycle, etc. Please consider it. If indeed there is no, please state the meaning of the symbol "/" at the bottom of the table.  
4. Discussion: Table 3 shows the future research directions. This is the most valuable content of this study. The authors need to add more explanation. The typical explanation must include specific suggestions, not a general one.
5. Others: There is no space before the percentage symbol (Lines 388, 390, 395, etc.). Table 3 has a typo "DG 12".

Author Response

We would like to sincerely thank the reviewer for taking the time to carefully read our manuscript and for providing valuable comments and suggestions, which have helped improve the scientific quality, clarity, and overall readability of our work. Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript addresses a highly relevant and timely topic at the intersection of artificial intelligence, Industry 4.0/5.0, circular economy and sustainable development, with a particular focus on SDG 12. The dataset is extensive (235 publications), the use of bibliometric tools (VOSviewer), geographical collaboration analysis and keyword co-occurrence mapping are appropriate and constitute a solid empirical basis. The study has clear potential for publication after substantial revision.

However, several major methodological and conceptual issues must be addressed before the manuscript can be considered for publication:

1. Search strategy and conceptual coverage
   The current search query is heavily centered on "supply chain" and artificially narrows the conceptual scope of the study. As a result, important research streams related to AI and sustainability (e.g., energy systems, smart cities, water management, healthcare, construction, or environmental monitoring) are largely excluded. This creates a structural bias in the results and contradicts the broad framing of Industry 4.0, Industry 5.0 and SDG 12 presented in the title and abstract.
   The authors are strongly encouraged to expand and clearly justify the search strategy, or explicitly redefine the scope of the study as supply-chain-dominated AI sustainability research.

2. Operationalization of SDG 12
   SDG 12 is currently treated mainly through technical environmental indicators (waste, emissions, water, energy). However, SDG 12 also includes behavioral, organizational and policy dimensions (e.g., sustainable consumption patterns, ethical production, transparency, circular business models). These aspects are currently underdeveloped.
   A clearer conceptual mapping between SDG 12 sub-targets and AI-related applications is strongly recommended.

3. Industry 5.0 conceptual framework
   While Industry 5.0 is frequently mentioned, its conceptual foundation remains weak. The manuscript does not sufficiently engage with the current EU-driven Industry 5.0 framework (human-centricity, resilience and sustainability). The current results primarily reflect Industry 4.0 research.
   The authors should strengthen the theoretical positioning of Industry 5.0, or more clearly acknowledge its still limited empirical presence in the dataset.

4. Discussion remains largely descriptive
   Although the results are clearly presented, the discussion is mostly descriptive. Critical dimensions such as:

• environmental rebound effects of AI,

• energy and resource footprint of data centers,

• rare earth material dependence,

• systemic risks and trade-offs,
  are largely absent.
  A deeper critical sustainability discussion is necessary to match the standards of Sustainability journal.

5. Conclusions partially exceed empirical support
   Some conclusions regarding Industry 5.0, ethical AI, and social transformation are stronger than what the bibliometric evidence directly supports.
   The conclusions should be more tightly aligned with the actual results.

6. Title and language issues
   The title contains a grammatical inaccuracy (“Evolving of the Research Focus”). This should be corrected (e.g., “Evolution of the Research Focus”). Minor language polishing is also recommended throughout the manuscript.

The study is promising and well-structured, but requires major methodological clarification, stronger conceptual grounding (especially for SDG 12 and Industry 5.0), and a deeper critical discussion. After these substantial revisions, the manuscript may become suitable for publication.

Comments on the Quality of English Language

The overall level of English is understandable and the manuscript can be followed without major difficulty. However, several sentences are overly long and stylistically heavy, and in some parts the terminology related to Industry 5.0, SDG 12 and sustainability concepts would benefit from clearer and more precise wording. Minor grammatical issues and phrasing inaccuracies are also present (including in the title). Therefore, careful language editing is recommended to improve clarity, precision and overall readability.

Author Response

We would like to sincerely thank the reviewer for taking the time to carefully read our manuscript and for providing valuable comments and suggestions, which have helped improve the scientific quality, clarity, and overall readability of our work. Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Thanks for the authors for considering reviewers' comments and recommendations.

Author Response

We sincerely thank the reviewer once again for their thorough review and constructive comments. 

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors:

 

Thank you for submitting the revision.

Please have a minor revision on these following comments:

1. No double dots in the Line 15.
2. No need to rewrite the backroynm of AI in the Lines 44, 64, 91, 97, and so forth. This already stated in Line 39. The same issue happens in the word of "Sustainable Development Goal. Please have a thorough checking on it.
3. Correct the writing format in Lines 80-89.
4. Be consistent in writing decimal point, such as Line 298 is using comma. Meanwhile, Line 359 is using dot to represent thousand.
5. Have a final proofread thoroughly.

Author Response

We sincerely thank the reviewer once again for their thorough review and constructive comments. Please find attached our point-by-point responses to your comments.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have responded appropriately to the main comments raised in the previous review round, and the manuscript has improved noticeably as a result. The scope of the study is now clearly defined as focusing on artificial intelligence in supply chains in relation to SDG 12, which resolves earlier concerns about conceptual overextension. The treatment of SDG 12 has been strengthened beyond purely technical indicators, and the discussion has been expanded to include more critical reflections on sustainability and systemic trade-offs.

The remaining issues are minor in nature and mainly concern language polishing and further tightening of the discussion and conclusions. These points do not affect the overall validity or contribution of the study. I therefore recommend acceptance after minor revision.

Comments on the Quality of English Language

The manuscript is generally clear and readable, and the language has improved compared to the previous version. Some sentences remain rather long and could benefit from minor stylistic editing to improve clarity and flow.

Author Response

We sincerely thank the reviewer once again for their thorough review and constructive comments.