Global Trends of Circular Economy and Innovation Research: A Bibliometric Analysis

The circular economy represents a paradigm shift in our approach to production, consumption, and waste management. Unlike the traditional linear economy, which follows a "take, make, dispose" model [1], the circular economy emphasizes sustainability through the continuous use of resources. This approach seeks to minimise waste and maximise the value derived from products and materials by keeping them in use for as long as possible [2]. Central to this model is the idea of a closed loop, ensuring that products are returned to the economy as valuable resources at the end of their lifecycle through recycling, refurbishment or remanufacturing [3, 4]. Innovation plays a crucial role in the transition to a circular economy. As the world's population grows and natural resources decline, the development of innovative technologies, business models, and practices that enable sustainable growth is essential [5]. Advances in circular strategies, which aim to reduce dependency on limited resources and mitigate environmental damage, are driven by innovations in product design, materials science and business practices. Advances in biodegradable materials, renewable energy and digital technologies enable improved resource management and reduced waste [6].

Recent bibliometric studies on the circular economy have made significant contributions to the field. For instance, Goyal et al. [7] and Camón Luis and Celma [8] explored general aspects of the circular economy, while Ruiz-Real et al. [9] examined the relationship between the circular economy and environmental issues. Martinho and Mourão [10] focused on the impact of the circular economy on economic development, and Negrete-Cardoso et al. [11] investigated its application in waste management. Additionally, Razmjooei et al. [12] studied the circular economy in the context of sustainability in maritime industries, and Correa et al. [13] explored reverse logistics within the circular economy.

Despite these contributions, there remains a notable gap in the literature regarding the intersection of the circular economy and innovation, particularly through bibliometric analysis. This research aims to fill this gap by conducting a comprehensive bibliometric analysis to identify key research themes, collaboration patterns, and emerging areas of focus within the realm of circular economy and innovation. The subsequent research questions (RQs) will be examined:

RQ1: What are the main characterisations and dynamic trends in the circular economy and innovation research?

RQ2: Who are the most prolific, collaborative authors, countries, and institutions in the field of circular economy and innovation research?

RQ3: Which journals have published the most research on the circular economy and innovation?

RQ4: Which keywords are most commonly utilised in research pertaining to the circular economy and innovation?

RQ5: What is the present state of knowledge generation regarding co-occurrence, collaboration, and co-authorship connections in the circular economy and innovation research?

RQ6: What are the major themes and future research direction of circular economy and innovation research and their evolution?

This study utilized bibliometric analysis to examine the publication of research on the circular economy and innovation, using data from the Scopus database. The objective was to present a comprehensive overview of the current global research trends in this field.

To address the research questions, the study is organised into the following sections. The "Introduction" section offers a succinct summary of the subject, encompassing the current comprehension of circular economy and innovation, previous research, the gap in knowledge, and the objective of the study. The "Research methodology" section outlines the specific approach employed in this study, encompassing bibliometric analysis and Biblioshiny techniques, as well as providing a flowchart and data analysis framework. The "Results" section provides a detailed analysis and answers the study questions mentioned earlier, the discussion and future research direction suggest potential themes for future research. Finally, the "Conclusion" section provides a summary of the contributions, limitations, and potential areas for future research.

3.1 Descriptive analysis

This section examines the research profile of circular economy and innovation from 2016 to 2024. As summarized in Table 1, current publication data, research trends, the most productive authors, frequently cited papers, publication sources, the most productive institutions and countries, and author keywords are taken into account.

Table 1. A summary of bibliographic information related to the circular economy and innovation

Description	Results
MAIN INFORMATION ABOUT DATA
Timespan	2016:2024
Sources (Journals, Books, etc)	233
Documents	401
Annual Growth Rate %	61.38
Document Average Age	2.21
Average citations per doc	20.82
References	22,248
DOCUMENT CONTENTS
Keywords Plus (ID)	1,713
Author's Keywords (DE)	1,093
AUTHORS
Authors	1,293
Authors of single-authored docs	46
DOCUMENT TYPES
article	255
book	3
book chapter	61
conference paper	45
editorial	5
erratum	1
note	3
review	27
short survey	1

3.1.1 Annual publication trends

The analysis of yearly publication trends considered total publications, total citations, citations per article, and citations per year for articles published between 2009 and 2024. Table 2 and Figure 3 illustrate the annual publication trends in the circular economy and innovation. Notably, the number of publications increased significantly from 30 articles in 2020 to 92 articles in 2024, indicating a dramatic upward trajectory in research output post-2020. It indicates evidence of a growing global attraction in academic discourse on the circular economy as a means to convert production and consumption models into more sustainable ones. Scholars are progressively investigating circular economy practices in the context of the COVID-19 pandemic, exploring them as a pathway to building more resilient economic models. Besides, advancements in research methods and publication processes have facilitated the dissemination of findings. This flow in scholarly output is also driven by enhanced collaboration among researchers from diverse areas, fostering a dynamic exchange of ideas.

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Figure 3. The annual publications trend

3.1.4 Most productive source titles

A total of 401 articles were published across various journals, Table 5 outlines the top source titles that published between 2016 and 2022. The journals Sustainability (Switzerland), Journal of Cleaner Production, and Business Strategy and the Environment emerged as the top three publishers, with 33, 25, and 18 publications, respectively, in the domain of circular economy and innovation, alongside total citations of 761, 1783, and 888.

Table 5. The most productive source title in the circular economy and innovation research

Note (s): TP = Total publications; TC = Total citations; h=h-index; PYS = Publication year start

3.1.5 Most productive countries

Following to the Scopus database, research documents on the circular economy and innovation were sourced from 79 countries, Table 6 lists the ten ranks of most productive countries, each contributing more than 20 papers. Among these, the United Kingdom stands out as the most productive, with 55 articles (8.49%), followed closely by Italy with 53 articles (8.18%). China and France each contributed 29 articles (4.48%), while Spain published 28 articles (4.32%). These findings indicate a heightened focus on the circular economy and innovation research in these countries compared to others.

Table 6. Most contributing countries of circular economy and innovation research

3.1.6 Most prolific institutions

Table 7 lists the twelve institutions with the highest output related to the circular economy and innovation research. The Technical University of Denmark and Universidade Nova de Lisboa were the leading institutions, each contributing 7 articles. Universidade do Oeste de Santa Catarina and Tampere University followed with 6 publications each. Collectively, these twelve institutions accounted for 66 articles, representing 16.41% of total publications, indicating a concentrated contribution to the field.

Table 7. Most productive institutions

3.1.7 Author keywords analysis

In bibliometric analysis, a word cloud of authors’ keywords serves as a visual representation of the most frequently employed terms within an article's keywords, facilitating the identification of prevailing themes in an author’s research. The size of each term in the cloud corresponds to its frequency of occurrence. Figure 4 presents the word cloud map of authors’ keywords in the circular economy and innovation research, revealing that "circular economy," "innovation," "sustainable development," "recycling," and "waste management" are consistently core research topics. This analysis indicates a relationship among sustainability, innovation, sustainable development, and circular economy, underscoring the interconnected nature of these concepts in research.

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Figure 4. Word cloud by author’s keywords

3.2 Network analysis of the circular economy and innovation research

Bibliometric mapping analysis method for identifying specific research fields and gaining a comprehensive understanding of the study area’s structure, including its themes, topics, terminology, and their interconnections. VOSviewer software can utilises a comprehensive approach that integrates clustering and mapping, primarily relying on standardised term co-occurrence to assess the strength of relationships between terms. Moreover, it serves as an effective instrument for conducting network research [15]. Also allows to visualise the conceptual landscape by colour-coding terms based on the year they first appeared in the scientific literature. The size of the font and surrounding rectangle indicates the popularity of the term; larger rectangles and fonts indicate terms that appear more frequently. In this study, we used VOSviewer to visualize co-authorship and collaboration networks and R Studio to examine keyword co-occurrences and conduct a thematic assessment of the topic of circular economy and innovation.

3.2.1 Co‐authorship analysis

The visualization of the co-authorship network revealed knowledge domain maps illustrating the principal author groups in the field of circular economy and innovation research. As depicted in Figure 5, each node represents an author, with the node size corresponding to the number of published articles. The links connecting nodes indicate the collaborative relationships between authors, with link thickness representing the strength of these associations. Insights derived from the co-authorship network can inform research institutions about potential collaboration opportunities, assist individual researchers in identifying areas for collaboration, and aid publishers in assembling editorial teams for special issues in journals or books. Figure 6 illustrates that collaboration among prolific authors is robust. The co-authorship network formed distinct groups, such as the red group, which includes Sehnem Simon (7 documents, 18 links), followed by Lopes de Sousa (3 documents, 16 links) in the orange group, with the red group serving as the core. The results suggest that most productive authors primarily engage in collaboration within the same organization, although such collaboration tends to be limited in scope, hindering effective international exchange and cooperation.

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Figure 5. Co-authorship network among productive authors

3.2.2 Countries collaboration network

The network visualization map is shown in Figure 6, Collaboration through co-authorship was identified in 79 countries (minimum threshold value of 1 document). The thickness of the connecting lines reflects the frequency of co-authorship between countries, The map indicates a satisfactory collaboration network, particularly among the United Kingdom, Italy, France, India, China, Spain, the United States, Brazil, Norway, Germany, and Portugal. Notably, the United Kingdom demonstrated extensive collaboration with countries across Europe, Asia, and North America, achieving the highest citation count of 2,847, along with 79 links and 56 documents. Conversely, countries such as Jordan, Tunisia, Singapore, Peru, New Zealand, Namibia, Luxembourg, Lebanon, Kenya, and Ghana exhibited less collaboration with other nations. This highlights two significant implications: firstly, it facilitates a more nuanced exploration of research topics; and secondly, it opens avenues for collaboration with new countries, encouraging engagement among researchers and institutions in these areas.

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Figure 6. Co-authorship collaboration network among countries

3.2.3 Keyword co‐occurrence network

Keywords serve as the focal point of publications, and the objective of keyword analysis is to identify significant research compositions in these fields. A network depicting the co-occurrence of keywords utilised by authors was employed to illuminate the research topics pertinent to this domain. This approach highlights frequently used keywords, represented by larger font sizes and circles. The lines connecting keywords reflect their degree of association [30]. For clarity, associated keywords are often grouped by colour. The absence of lines between keywords indicates a lack of established connections. Terms positioned closer to the centre of the network diagram signify a higher degree of co-occurrence, implying a stronger correlation.

To investigate associated keywords in the circular economy and innovation research, Figure 8 identifies three thematic clusters: (i) Circular Economy, (ii) Innovation, and (iii) Recycling and Waste Management, each represented in distinct colours. The circular economy cluster occupies the centre of the network, indicating it is a significant theme explored by prior scholars. Each colour corresponds to a group of related concepts, illustrating how different aspects of the circular economy are interlinked (Figure 7).

1. Red Cluster keywords: circular economy, sustainable development, economics, economic and social effects, economic growth, government, investments, and decision making. This cluster examines circular economy, economics and society. It emphasises economic growth, policy, and government involvement in the sustainable development. Investment and technical innovation are linked, demonstrating how financial and regulatory support are essential for the circular practices.

2. Green Cluster keywords include waste management and environmental impact keywords include municipal solid waste, food waste, plastic waste, greenhouse gases, gas emissions, carbon, and life cycle. The green cluster focuses on waste management and the environment. It discusses municipal solid waste, plastic trash, greenhouse gas emissions, and carbon management. This cluster is crucial to understand how waste disposal and life cycle analysis support the circular economy.

3. Yellow Cluster keywords include innovation, eco-innovation, recycling, economic conditions, strategic strategy, and social innovation. This cluster emphasises innovation in the circular economy practises. Eco-innovation links sustainable technology and process innovations to economic conditions and strategy. The integration of social innovation emphasises societal change in the circular practices.

4. Blue Cluster keywords include business model innovation, business models, environmental sustainability, business development, technology advancement, supply chains, and manufacturing. The blue cluster covers business models and circular economy technology. Innovation in business models like product-as-a-service or supply chain optimisation can improve sustainability and economic performance.

5. Grey Cluster includes product design, production, open innovation, and technology innovation. This smaller cluster emphasises the circular economy product design and manufacturing. It links product design to technology and open innovation, claiming that the circular concepts are essential for sustainability.

6. At the network's centre, the circular economy and sustainable development appear as the most connected and fundamental themes. These phrases link economic, environmental, and social components of the circular economy framework, placing them in the centre of all other concepts. The keyword of circular economy is superposed on sustainable development, technological innovation, economic, supply chain, government, open innovation and economic and social effect representing the closeness among them. Furthermore, in the second network of the innovation, the linked keywords are sustainability, eco-innovation and environmental economics. The third link is recycling and waste management, the linked keywords are life cycle, carbon, municipal solid waste, food waste and greenhouse gases. This analysis highlights the importance of the circular economy and innovation research and has proven the field as an emerging field.

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Figure 7. Author’s keywords co-occurrence analysis

3.3 Thematic evaluation

Biblioshiny software was used to analyse the author’s keywords of the circular economy and innovation research and evaluate the main research topics from 2016 to 2022.

Figure 8 provides an overview of current research and future trends in the circular economy and innovation, as illustrated by the themes in the four quadrants. The Motor Themes are the driving forces in this field, highlighting areas that are both well-researched and critical to the implementation of circular economy practices. Topics such as waste management, food waste, carbon management, and greenhouse gases are not only mature but also pivotal in advancing the circular economy. The Niche Themes represent specialised areas that, while not widely applicable, are important within specific contexts. For instance, the construction industry, ecosystem management, and wastewater treatment are essential within certain sectors, even if they may not be as broadly relevant to the circular economy as a whole. The Basic Themes form the foundation of the circular economy, representing essential concepts that are widely applicable but may require further development or research. Core topics like the circular economy itself, sustainable development, and environmental economics are fundamental to the field, indicating their broad importance but also suggesting that more detailed work is needed to advance in these areas. The Emerging could either be new areas that are just beginning to gain traction or older topics that are becoming less relevant. In this case, themes related to business model innovation and manufacturing may represent emerging areas of interest within the circular economy that are still in the early stages of research or practice.

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Figure 8. The strategic thematic map based on author’s keywords

The conceptual structure map, derived from Multiple Correspondence Analysis (MCA) and shown in Figure 9, illustrates two key groups, each represented by different colours, which direct the logical construct of the circular economy and innovation studies. The Red group focuses on themes related to business models and innovation within the circular economy, with particular emphasis on collaboration and upcycling. The close relationship between collaboration and open innovation suggests that successful circular business models often rely on these collaborative efforts and practices. Upcycling further highlights the importance of adding value to waste materials as part of these models, aligning with the overall goal of sustainability. The Blue group is broader, encompassing a wide range of concepts related to the circular economy, eco-design, and sustainable practices. The presence of terms like SMEs (Small and Medium-sized Enterprises), resource efficiency, and eco-design suggests that this cluster emphasizes the practical implementation of circular economy principles, particularly in smaller businesses and through design practices. The inclusion of environmental sustainability and innovation underscores the strong focus on these areas as drivers of the circular economy, further supported by related concepts like waste management, recycling, and eco-innovation. The positioning of SMEs and resource efficiency indicate that these are crucial elements for achieving sustainable business practices, especially in smaller enterprises.

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Figure 9. Conceptual structure map based on author’s keywords

The findings of the study make a significant contribution to the existing body of knowledge by shedding light on the current research trends in the fields of circular economy and innovation. A total of 401 papers on these topics were analysed, employing VOSviewer software to construct a scientific mapping and R software for thematic evaluation. The research explores key characteristics and dynamic trends within the literature, including the most prolific authors, collaborative networks, leading countries, and prominent institutions. Additionally, the study identifies the journals that have published the most research and provide insights into the state of knowledge generation, particularly in terms of co-occurrence, collaboration, and co-authorship patterns in the circular economy and innovation studies.

Finally, this study highlights thematic evaluations and presents thematic maps as a guideline for future research such as the Development of sustainable business models, Technological advancements for waste valorisation, Product design and innovation, Collaborative innovation networks, Policy and regulation-induced innovation, and Digital transformation for Circular Economy. The findings of this research are expected to assist scholars in identifying gaps within the field of the circular economy and innovation by extending and delving into specific innovations that can circularity in various, whether service or industrial operations. The limitation of this study is the exclusive reliance on the Scopus database as the primary source for document retrieval. Although Scopus is comprehensive database for scholarly works, it still has limitations in its coverage. Future studies would benefit from incorporating additional databases for example WoS etc., as integrating multiple databases is likely to enhance the widely and significance of outcomes.