Corrosion inhibition effects of organic compounds on carbon steel research progress: a visualization analysis based on CiteSpace

This study systematically reviews the progress of research on the corrosion inhibition effects of organic compounds on carbon steel since 2002, using the CiteSpace bibliometric tool. Through the analysis of 2,264 articles from the WOS (Web of Science) and Scopus databases, our team delved into aspects such as annual publication volume, authors, institutions, countries and keywords which helped identify the current research focus in this field. In particular, the protective efficacy of organic compounds on carbon steel in acidic environments has been highlighted. It is evident that the integration of coating technology, the development of organic compound derivatives and the extraction of green organic compounds have emerged as new research hotspots in this field. This study not only comprehensively evaluates the means and methods of assessing the corrosion inhibition performance of new organic compounds but also further specifies the main directions for future research in this field. These include composite organic coatings, targeted development of new organic compounds, development and application of green organic compounds from plants and corrosion inhibition mechanisms of organic compounds on other metal materials. This study not only provides a thorough and in-depth review of the history and current status of this field but, more importantly, clarifies specific directions for future research in this area. The aim of this research is to provide strong theoretical support and practical guidance for subsequent researchers, promoting future development of this field.


Introduction
Carbon steel, due to its excellent mechanical properties and relatively low cost, has become the preferred material for all sorts of containers, pipelines and mechanical parts [1,2].However, the performance of carbon steel in corrosive environments is not satisfactory.Its poor corrosion resistance significantly affects the reliability and lifespan of machinery parts made of carbon steel [3][4][5].To address this issue, the industry often uses corrosion inhibitors to slow down the corrosion rate of carbon steel [6][7][8].
Traditional industrial corrosion inhibitors are primarily inorganic salts, such as nitrates, chromates and phosphates.They mainly passivate the metal surface by forming a stable oxide film to resist the corrosive environment [9,10].However, excessive use of these inhibitors can have significant impacts on the global ecosystem, leading to various environmental and health issues [11][12][13].
Given this, organic compounds as corrosion inhibitors have gradually attracted the attention of researchers.They are characterized by their low cost, ease of synthesis, high efficiency, environmental friendliness and nontoxicity [14][15][16][17].These organic compounds mainly include phenols, alcohols, ketones, steroids, saponins, aldehydes and fats [18].They can physically or chemically interact with the metal surface or have a combined effect, blocking active sites, thereby limiting the reaction rate of the cathode, anode, or both [19], which results in inhibition of corrosion.Specifically, physical interactions refer to the adsorption of inhibitor molecules on the metal surface through van der Waals or Coulombic forces [20].Chemical interactions involve sulfur (S), nitrogen (N), phosphorus (P), oxygen (O) and conjugated groups (such as functional groups, heteroatoms,

Research methods and analysis tools
Bibliometrics is a research method and discipline that studies the informetric characteristics of scientific literature, development trends and the relationship between research and between literature.It primarily reveals the scale, fields, popular research directions and influence of scientific research through statistics, measurement and analysis of literature information.This study conducted a review of the corrosion inhibition effect of organic compounds on carbon steel in corrosive environments using the CiteSpace software version 6.1R3 on the Windows 11 platform.CiteSpace is an information visualization software developed in the Java language.This software, combined with citation analysis data and information visualization technology, generates clear framework knowledge maps and explores the key paths and knowledge turning points in the evolution of scientific fields.It helps researchers intuitively analyze the development background, research hotspots and development trends of the research field [34].

Annual publication volume analysis
The volume of literature published is seen as an important indicator reflecting the activity and attention of a research field [35].By analyzing the volume of literature published, the research history and development trend of the field can be depicted.Figure 1 shows the annual publication volume in the research field of the corrosion inhibition effect of organic compounds on carbon steel in corrosive environments, as counted by CiteSpace. of the total, reflecting that the field was in its initial exploration and accumulation stage.

Steady Growth Phase (2008-2014):
The number of publications in this period accounted for 25.93% of the total.The number of publications showed minor fluctuations but an overall upward trend, especially in 2011, when there was a small peak with 107 papers published.This phase can be considered a steady development period for the field.
3. Significant Growth Phase (2015-2022): During this phase, the publication volume accounted for 66.12% of the total, with 2019 seeing the highest number of publications, totaling 265 papers.Although there was a decline in the number of publications between 2020 and 2022, which might be partially related to the outbreak of the COVID-19 pandemic in early 2020, the research remained highly active.
Considering the development process and changes mentioned above, this study believes that with the popularization of industrial manufacturing technology and the gradual acceptance of the 'green industry' concept, the pollution problem related to corrosion inhibitors has become an issue that cannot be ignored.Therefore, more and more researchers have begun to focus on the research of the corrosion inhibition effect of organic compounds on carbon steel in corrosive environments, seeking for more environmentally friendly and efficient corrosion solutions.

Author collaboration network analysis
The author collaboration network graph is a powerful tool that can reveal the core authors in a research field and their collaboration and citation relationships [36].Using the author analysis function of CiteSpace, this study constructed a collaboration network for the research field of the corrosion inhibition effect of organic compounds on carbon steel in corrosive environments (as shown in figure 2) and related author information (see table 1).
Figure 2 includes 759 nodes and 893 lines, where each node represents an individual author.The size of the node is proportional to the number of articles published by the author.The lines and their width symbolize the collaboration relationships and collaboration strength between authors of published literature.The network density of figure 2 is 0.0031, reflecting the degree of direct connection between nodes.According to the analysis of figure 2, eight relatively stable research teams were formed in this research field.Notably, the Hammouti B team had the broadest collaboration and the largest research scale, focusing mainly on the impact of different organic compounds and their derivatives on the corrosion resistance of carbon steel [37][38][39].However, there is still a lack of key communication and collaboration hubs between research teams.
Table 1 lists the basic information of the top 15 authors ordered by publication volume, where 'Count' indicates the total number of publications for each author.'Betweenness centrality' quantifies an author's ability to act as a 'bridge' connecting different research groups in the entire collaboration network.Specifically, the more often an author acts as a 'mediator', the higher their betweenness centrality.Such authors usually show greater potential for interdisciplinary collaboration and may be key figures in transformative scientific discoveries [40].In figure 2, these core authors are marked with purple circles.If an author's betweenness centrality is less than 0.01, it is recorded as 0 in the table.As shown in table 1, Quraishi, M A is the author with the highest publication volume, who published a total of 61 papers.Verma, Chandrabhan has the highest betweenness centrality, reaching 0.11.These data indicate that the above core authors play a crucial role in this research field, acting as bridges for effective academic communication between research groups.
In summary, the research on the corrosion inhibition effect of organic compounds on carbon steel in corrosive environments has gradually gained attention from scholars.Although a core author team has gradually formed in this field, the depth and breadth of research still need to be further expanded.

Institutional collaboration network analysis
To systematically assess the contributions and development trajectories of various research institutions, it is necessary to conduct statistical analysis of the publishing institutions [41].In the institutional collaboration network map (figure 3), there are a total of 524 nodes and 457 edges, with a network density of 0.0033.From figure 3, it can be identified that seven mature collaboration institutions already formed in this research field.Notable institutions include the Department of Chemistry, King Fahd Univ Petr & Minerals, Chinese Acad Sci and the Egyptian Petr Res Inst, among others.
Table 2 lists the information of the top 15 institutions by publication volume.Among them, the Department of Chemistry has the highest publication volume, reaching 106 papers, accounting for 4.68% of the total volume.Its betweenness centrality is 0.07, ranking fourth, indicating that this institution is a core research institution in this field.Univ Ibn Zohr (with a betweenness centrality of 0.27), Univ Ibn Tofail (0.12), Chinese Acad Sci (0.08) and others have shown high betweenness centrality.This means that these institutions not only act as bridges in the research network but also have significant advantages in information circulation and control [42].[43,44].Our team used CiteSpace software to draw the national collaboration network (figure 4) and detailed statistics of the top 15 countries by publication volume (table 3).
According to the analysis of the national collaboration network in figure 4, there are 88 nodes and 105 edges, with a network density of 0.0274.These data reveal that an international collaboration network with a certain scale and structure has formed.Notably, countries like the People's Republic of China, India, Egypt, Morocco, Iran and Malaysia occupy central positions in some collaboration groups.As shown in table 3, research in this field is mainly concentrated in developing countries prevailing in agriculture and manufacturing.China has the highest publication volume, totaling 405 papers, accounting for 17.89% of the total.However, it's worth noting that China's betweenness centrality (0.08) is significantly lower than countries like Saudi Arabia (0.71), Morocco (0.66), Niger (0.12), South Africa (0.27) and Algeria (0.27).
Based on the above analysis, we suggest that while maintaining high output, China should actively seek collaboration with other countries to improve its betweenness centrality in this research field.This will not only further enhance China's research level in this field but also promote the rapid and healthy development of the entire field.

Research hotspot analysis 4.1. Keyword co-occurrence analysis
Keywords in literature not only carry core information but are also crucial for capturing the essence of the content and understanding the main theme of articles.Therefore, keyword research plays a foundational and guiding role in understanding a research field [45].To systematically and deeply understand the core and trends of this research field, this paper uses CiteSpace software to perform a co-occurrence analysis of keywords.After cleaning and integrating the original keywords, removing invalid keywords and merging semantically similar keywords, we finally obtained the keyword co-occurrence network map (figure 5) and detailed information of the top 20 keywords (table 4).
In figure 5, each node represents a keyword, and the size of the node reflects the frequency of the keyword's appearance in the literature: the larger the node, the higher the frequency of the keyword, implying its greater importance in the research field.The lines between nodes reveal the co-occurrence relationship between two keywords, and the thickness of the line represents the strength of their co-occurrence, i.e., the frequency with which they appear together in the same article [46,47].
Through a detailed analysis of figure 5 and table 4, we can clearly identify a series of high-frequency and core keywords in the research field of organic compounds' inhibitory effects on carbon steel in corrosive environments, such as 'adsorption', 'inhibitor', 'derivatives', 'behavior', 'hydrochloric acid', 'sulfuric acid' and 'electrochemical corrosion'.The frequency of these keywords exceeds 300 times, or their betweenness centrality exceeds 0.10, which clearly indicates the current research hotspots and focus areas in this field.

Keyword clustering analysis
To clarify and delve deeper into the themes and core issues in this research field, this study conducted a detailed clustering analysis of keywords using the Log Likelihood Ratio (LLR) algorithm.Based on the co-occurrence relationship of keywords, we calculated a clustering modularity Q = 0.7548 (significantly greater than 0.3) and an average silhouette S = 0.8749 (significantly greater than 0.7).These numerical indicators prove that the clustering structure derived from this study is significant, reasonable and credible [48].
With careful analysis, we identified 26 unique research categories in this field and listed the top 10 representative clustering information in table 5.The Cluster id starts from 0. The smaller the number, the more keywords the cluster contains, indicating the greater importance of the cluster theme.The Cluster name defines the theme label of the cluster.The Size indicates the number of keywords contained in the cluster, where custers with size>10 are deemed valid.The Silhouette value is used to evaluate the closeness of keywords within the cluster.Silhouette>0.7 indicates good internal cohesion, i.e., successful clustering.The Top terms list the main keywords contained in the cluster.According to the clustering details in table 5, we can tell that the major background environment used in corrosion research is acidic, indicating that the corrosiveness of acidic environments to carbon steel is much higher than that of neutral and alkaline environments [49].We can also identify the five prevailing research categories in this field: 1. Weight loss methods, electrochemical tests and molecular dynamics simulations are the three major methods used in this field.By combining experimental and theoretical analysis, researchers observe the corrosion inhibition process and results in a more efficient, intuitive and convenient way, thereby fully revealing the adsorption corrosion inhibition mechanism of organic compounds on carbon steel in a corrosive environment.
2. Researchers are concerned with the role of composite organic coatings in corrosion protection of carbon steel.Mixing organic compounds with existing coatings improves the performance of the current coatings.The corrosion inhibition effect of Schiff bases mixed into coatings on carbon steel has received widespread attention from scholars.This method has advantages such as simple process, mild reaction conditions, harmless reaction products and high efficiency [50].
3. The development of new organic compounds and their derivatives has also received widespread attention from researchers.For example, triazoles and benzimidazoles have good corrosion inhibition performance and high development potential, becoming important research objects.
4. Researchers also focus on using plant extracts to manufacture green organic corrosion inhibitors.Such a manufacturing method is greener, safer and more environmentally friendly compared to industrial corrosion inhibitors, conducive to sustainable environmental development.

5.
Research content has expanded from carbon steel corrosion to corrosion inhibition issues of various metals such as stainless steel, copper and aluminum, showing that the research horizon in this field is continuously expanding.

Keyword burst analysis
'Keyword burst' refers to a significant increase in the frequency of a keyword within a specific period, usually reflecting the current research hotspots and frontier trends in the field [51].This study compiled and organized the top 15 bursting keywords in this field in table 6.In table 6, 'Year' represents the year when the keyword first Considering the data from tables 4-6, the frontier research topics in this field can be summarized as: 1. Evaluation and application techniques of organic compounds in adsorption corrosion inhibition.
2. Research on the corrosion inhibition effects of new composite organic coatings.
3. Synthesis of new organic compounds and their derivatives.
4. Research on green organic corrosion inhibitors from plant extractions.

Exploration of the corrosion inhibition mechanism of organic compounds on metals other than carbon steel.
These focus areas are expected to become key factors in advancing the development of this direction.

Analysis of future development trends
By using the CiteSpace software, the team conducted an in-depth analysis of the current status of research on the effect of organic compounds in corrosion environments.Combined with multiple specific examples, we aim to provide a comprehensive discussion and insights on the future development direction of this field.

Research on evaluation methods and technologies for the corrosion inhibition of organic compounds
In terms of the study of the corrosion inhibition effect of organic compounds on carbon steel, the methods and technologies for evaluating the corrosion inhibition effect are a key research focus.Commonly used evaluation methods and techniques include physical measurement analysis, electrochemical analysis, microscopic surface morphology analysis, molecular modeling, etc.The weight loss method (WL) is a widely used physical measurement and evaluation method, which quantifies the corrosion rate based on the weight loss of the sample before and after corrosion, quantitatively evaluating the effect of corrosion or corrosion inhibition from a macroscopic level.
Electrochemical testing techniques, including electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP), are widely recognized as efficient, convenient and accurate techniques for evaluating the corrosion inhibition ability of organic compounds [52].
During the experiment, researchers often use scanning electron microscopy (SEM), atomic force microscopy (AFM), energy-dispersive x-ray spectroscopy (EDS), furier transform infrared spectroscopy (FT-IR), x-ray photoelectron spectroscopy (XPS), X-ray diffractometer (XRD), nuclear magnetic resonance spectroscopy (NMR), etc, to deeply analyze the microscopic morphology and chemical composition changes of the carbon steel surface, thereby further revealing the corrosion inhibition mechanism of organic compounds.At the same time, theoretical analysis methods have also attracted the attention of researchers, such as adsorption isotherms, thermodynamic parameters, density functional theory (DFT), Monte Carlo simulation (MC), molecular dynamics simulation (MD), quantum mechanics (QM), etc Molecular modeling help researchers understand and explain the corrosion inhibition mechanism of organic compounds and their adsorption forms on metal surfaces from a microscopic level.Some scholars verified the existence of the adsorption layer by comprehensively using the above methods and clarified that the adsorption process presents mixed-type adsorption characteristics [53].For more research cases, see table 7.
Based on the comprehensive analysis of table 7, we observed that more and more researchers tend to use WL, electrochemical technology, surface morphology analyzers and theoretical analysis methods in combination to ensure that the experimental verification of the corrosion inhibition process is more accurate and reliable.Practical usage has proved that this comprehensive verification method is accurate, efficient and widely applicable.

Research on the synthesis of new coatings with corrosion protection
Coating technology is an important means of metal corrosion protection.In terms of protection mechanism, coatings can mainly inhibit the corrosion process of metals through anodic passivation, cathodic protection, electrolytic inhibition and active corrosion inhibition, etc [59].The current research focuses mainly on improving the corrosion inhibition effect of existing coatings by adding organic compounds.After the coating is prepared, it can be applied to the metal surface through techniques such as casting, spraying, impregnation coating, spin coating and electrodeposition, thereby forming a stable protective layer on the metal surface to achieve effective corrosion protection.
Taking the research of Sanaei Z, et al as an example [60], a green hybrid organic pigment made by Cichoriumc intybus L leaf extract and zinc cations was studied.The prepared pigment was mixed with epoxy ester coatings.PDP and EIS methods were used to study the effect of hybrid pigments on the corrosion resistance of epoxy ester coatings.The hybrid pigments were characterized by thermogravimetric analysis (TGA) and FT-IR.The results show that the addition of hybrid pigments significantly improves the barrier and active corrosion resistance performance of epoxy ester coatings.In addition, the results of MD and QM studies also confirmed the adhesion of organic inhibitors to the steel surface.This case reveals a new coating synthesis method that effectively protects metal materials.For more research cases and detailed data analysis on this topic, please refer to table 8.

Research on the synthesis of new organic compounds and their derivatives with corrosion inhibition
Studies have shown that donor heteroatoms (such as S, N, P, O), conjugated groups and chain length parameters in organic compounds can significantly affect their efficiency as corrosion inhibitors [66][67][68][69][70][71].Therefore, by specifically replacing functional groups, new organic compounds and their derivatives can be precisely designed and synthesized, optimizing them into efficient corrosion inhibitor molecules.This not only has significant practical significance but also is budget and time saving.
Taking the work of Xu Y H, et al as an example [72], a new beta-amino alcohol compound named TDB was successfully synthesized by adding 4-(2-Aminoethyl) benzenesulfonamide, ethylene glycol diglycidyl ether and methanol in a specific ratio.Using PDP and EIS, the corrosion inhibition effect of TDB on low carbon steel in 0.5 M H 2 SO 4 solution was studied.Experiment results revealed that TDB can effectively inhibit the hydrogen evolution reaction on the cathode and the metal dissolution process of the anode.Moreover, even at a lower concentration (10 mg l −1 ), the corrosion inhibition efficiency of TDB on carbon steel still reached 90.7%.Further analysis of SEM and XPS results supported the hypothesis that inhibitors inhibit corrosion through adsorption.In addition, DFT calculations further verified the formation of a stable adsorption layer on the low carbon steel surface by the aromatic ring and multiple heteroatoms in the TDB molecular structure.
In summary, it can be clearly understood that precisely replacing existing atoms or introducing new atoms in target organic compounds can significantly enhance their adsorption capacity and corrosion inhibition effect on carbon steel in a corrosive environment.Some compounds, even at low concentrations, also show excellent inhibition efficiency.Currently, more and more scholars are focusing on the synthesis of new organic compounds and their derivatives.This trend undoubtedly opens up new research horizons and practical spaces for the development and application of efficient organic corrosion inhibitors in the future.For specific research cases and data analysis, please refer to table 9. 5.4.Research on organic corrosion inhibitors derived from plant extracts Even though synthesizing new organic compounds has made significant contributions to enhancing the efficiency of organic corrosion inhibitors, which has a superior inhibitory performance even at low concentrations, a comprehensive evaluation from synthesis processes, economic cost and environmental protection suggests that using plant extracts to prepare organic corrosion inhibitors has greater potential.Natural plants contain a variety of organic compounds with anti-corrosion properties.These compounds are considered ideal raw materials for the preparation of green, effective and low-cost organic corrosion inhibitors [78,79].Therefore, researching how to extract effective organic compounds from natural plants and turn them into organic corrosion inhibitors has not only high scientific value but also significant practical applications [80,81].
Taking the research of Palaniappan N, et al as an example [82], the team used rapid ultrasonic extraction to extract ethanol-soluble organics from the roots and stems of Catharanthus roseus.Using techniques like WL, PDP, EIS, they verified the inhibitory effects of these extracts on metals.Through SEM, EDX, FT-IR, AFM, etc, they closely observed and analyzed the surface morphology and microstructural changes of carbon steel during the corrosion process.The results revealed that the extracts from Catharanthus roseus showed significant mixed-type inhibitor characteristics.Notably, the inhibitory efficiency of the stem extract of Catharanthus roseus was four times that of the root extract, indicating the high feasibility of preparing organic corrosion inhibitors from plant extracts.
Other results are listed in table 10.Based on the abovementioned findings, we can clearly conclude that the use of plant-extracted organic compounds in preparing green organic corrosion inhibitors is highly feasible.As more and more scholars extract highly effective and eco-friendly organic compounds with anti-corrosion properties from nature, this research direction has gradually become an important development trend in the study of organic corrosion inhibitors.Given the diversity of plant species in nature, future research teams could continue to explore and discover more efficient and convenient green organic corrosion inhibitors.

Research on the corrosion inhibition of organic compounds on other metal materials
With the widespread use of metal products other than carbon steel, such as stainless steel, copper and aluminum, the corrosion of these materials in specific environments has become a pressing issue.In addition to research on the corrosion mitigation of carbon steel, recent studies on the corrosion inhibition of organic compounds on other metal materials like stainless steel, copper and aluminum have also garnered attention [88][89][90][91][92].
For instance, in the work of Melian R, et al [93], it was found that 5,5'-dithiobis-(2-nitrobenzoic acid) (ER) and sodium sulfite (SUL) could significantly inhibit the corrosion of aluminum alloy 2024-T3 in a 3.5% sodium chloride solution.Using electrochemical testing techniques like PDP and EIS, they determined that these inhibitors mainly functioned as cathodic inhibitors.Notably, the inhibitory efficiency was positively correlated with the concentration of the inhibitor.For example, when the concentration of ER comes to 10 −2 M, the corrosion inhibition efficiency can reach 93%.When the concentration of SUL rises to 10 −2 M, the corrosion inhibition efficiency soars to 98%.Further SEM analysis supported the hypothesis that the inhibitors functioned through adsorption to inhibit corrosion.Additionally, MD calculations further verified the adsorption behavior of these compounds theoretically.
In conclusion, organic compounds can effectively slow down the corrosion rate of metal materials such as stainless steel, copper and aluminum in specific corrosive environments.Therefore, the development and application of organic corrosion inhibitors not only are necessary for carbon steel but also have significant implications for the corrosion mitigation of other metal materials.This will undoubtedly become an important research direction in future environmental protection and sustainable resource utilization strategies.For more reletive research cases and detailed data, please refer to table 11.

Conclusions
This study is dedicated to a thorough discussion of the current status and trends of the corrosion inhibition effects of organic compounds on carbon steel in corrosive environments.To achieve this goal, we scientifically and systematically referred to numerous literature sources and utilized the scientometric analysis tool CiteSpace to conduct a detailed and precise visual analysis of 2,264 literature records in the WOS core database and Scopus database.This scientometric study clearly depicts the knowledge structure and development trajectory of this field.

Main findings
Since 2002, the research on the corrosion inhibition effects of organic compounds on carbon steel has gradually become a focal point in academia.Especially after 2008, this research area has been significantly deepened.During this period, a group of relatively stable academic teams and cooperative institution networks were formed.Notably, the team of Hammouti, B and the Department of Chemistry exhibited significant influence.Moreover, developing countries, especially China, have played a crucial role in this field of research, even though international collaborations are relatively limited.The current research focus is mainly on the corrosion inhibition effects of organic compounds in acidic environments, yet research on coating technology, the development of new organic compounds and the study of green organic corrosion inhibitors are also gradually gaining attention.

Future research directions
With the increasing global attention to corrosion issues, this research field is expected to delve deeper into the potential and application of organic compounds as corrosion inhibitors in the future.Firstly, the research should explore in depth the corrosion inhibition effects of different organic compounds on carbon steel in specific environments (such as acidic, seawater, etc), including analyzing the relationship between the structure of different organic compounds and their corrosion inhibition performance.Secondly, the combined use of coating technology and corrosion inhibitors will also become an important direction for future research.Future research should explore how to effectively integrate organic compounds into coatings to enhance their cumulative effect in corrosion protection.This may include developing new composite organic coatings, improving the adhesion, stability and compatibility of the coating with the substrate.
Thirdly, future research needs to focus on the design and evaluation of green and environmentally friendly organic corrosion inhibitors.From a sustainable development perspective, priority should be given to searching for eco-friendly, low-toxic or non-toxic organic compounds or exploring the corrosion inhibition effects of organic compounds extracted from plants, ensuring that while effectively controlling corrosion, potential risks to the environment and human health are minimized.
Lastly, future research needs to further clarify the potential and mechanism of organic corrosion inhibitors on other important industrial metal materials (such as stainless steel, aluminum alloys, etc), which will help promote a more comprehensive knowledge system and widespread application in this field.

Research limitations and suggestions
This study is constrained by the CiteSpace tool used and the scope of the data sample, so the research results may have certain limitations.For future research, integrating data from a wider range of sources and considering the use of multiple analysis and visualization techniques will be key to further enriching and refining the knowledge structure and development trends of this field.At the same time, the toxicity and ecological impact assessment of new corrosion inhibitors also need to be paid sufficient attention in future research.Therefore, it is suggested that future research should take the collaboration with the industrial sector into consideration to ensure the usage and promotion of research results.

Figure 1 ,
Figure 1, three distinct development phases in this research field can be identified: 1.Initial Development Phase (2002-2007): During this phase, the number of publications accounted for 7.95%of the total, reflecting that the field was in its initial exploration and accumulation stage.

Table 1 .
Statistics of the top 15 authors in terms of publications in the research area.

Table 2 .
Top 15Institutions in terms of number of publications in the research area.

Table 3 .
Top 15Nationals in terms of number of publications by research area.

Table 4 .
Statistics of top 20 keywords cited in research areas.

Table 5 .
Statistics of top 10 keywords clustering information in research area.Density functional theory, Raman spectroscopy, Nanocomposite coating appeared, while 'Begin' and 'End' respectively indicate the start and end years of the keyword's significant increase in frequency.Observing table 6, we find that 'Iron' has a burst period lasting 12 years, with a burst strength of 48.6597.Such a long duration and significant burst strength suggest that with industrialization, the widespread application of steel in various industries and research on corrosion prevention of steel in corrosive environments have received significant attention from researchers.Secondly, the keyword 'acid inhibition' has a burst strength of 29.9736, indicating that the corrosion inhibition effect of carbon steel in an acidic environment is a current research focus.Based on the previous analysis, future research directions may revolve around the following keywords: corrosion inhibition, triazole derivatives, Schiff base compounds, weight loss method, acid corrosion, molecular dynamics, Monte Carlo method, green corrosion inhibitors and so on.

Table 6 .
Statistics of top 15 keywords cited in the research area.

Table 7 .
Research cases of evaluation methods and evaluation techniques for corrosion inhibition of organic compounds.

Table 8 .
Research cases of synthesizing new coatings with corrosion protection effects.

Table 9 .
Research cases of synthesizing new organic compound derivatives with corrosion inhibition effects.

Table 10 .
Research cases of extraction of green compounds with corrosion inhibition effect in plants.

Table 11 .
Research cases of corrosion inhibition effect of organic compounds on other metal materials.