Nano zero valent iron in the 21st century: A data-driven visualization and analysis of research topics and trends

Nano zero valent iron (nZVI) is an environmental functional material with a core-shell structure, which has been widely used for environmental remediation. The published literatures in the Web of Science Core Collection database from 2000 to 2021 were used to reveal crucial information and guidance on what has been investigated and what the changes in research interests using a bibliometric method, in order to better understand the developments and trends in research on nZVI. The knowledge structure, hot issues, and trend directions in the field of nZVI were analyzed using VOSviewer, Bibliometrix, and Microsoft Charticulator. Keywords copolymerization analysis revealed four main directions of nZVI research, including groundwater remediation, in situ soil remediation, adsorption-related research, modification of nZVI and innovative applications. The heavy metal Cr(VI) is the pollutant that has received the most attention in the field of nZVI. “Electron transfer”, “S-nZVI (Sulfidated nZVI)" and “copper” are the research theme trends. Meanwhile, we summarize the mechanisms of nZVI for decontamination, different typical modification methods, the application disadvantage and make some suggestions for the field of nZVI. This work will provide insights for future research and practical applications related to nZVI. [Display omitted] •Changes in the knowledge structure and thematic trends of nZVI are revealed.•The theme trends at the present are “Electron transfer”, “S-nZVI” and “copper".•The mechanism, drawbacks and improvement paths of nZVI for pollutant removal are summarized.•Provide future directions and suggestions for the investigation of nZVI.