Bibliometric analysis of hotspots and frontiers on remediation materials for heavy metal contaminated soils

Based on the database of Web of Science (WoS) Core Collection and China National Knowledge Infrastructure (CNKI), the literature in the past 20 years was searched by using literature metrology and visual analysis software to reveal the development context, research hotspots and development direction of the research field of heavy metal contaminated soil remediation materials at home and abroad. The results showed that compared with 2001-2004, the number of articles published in the field of heavy metal contaminated soil remediation materials in 2013-2016 and 2017-2020 increased significantly by 1302% and 2201% respectively, showing rapid growth. Compared with foreign research, although China started late in this field, it had developed rapidly. Keywords hot spot analysis showed current pollution remediation research focused on remediation of farmland soil, remediation of heavy metals cadmium and lead, and application of immobilized materials. Through keywords cluster analysis, screening and application of immobilized materials was a hot topic of current research, especially the repair mechanism and effect evaluation of immobilized materials were the focus and difficulty of this topic. At present, research on remediation materials for heavy metal pollution in farmland is developing rapidly and functional modification of immobilized materials and their application in farmland are expected to achieve good results in remediation. Moreover, the research and development and application of "green pollution-free" and "safe and sustainable" remediation materials are becoming a research hotspot at present and in the future.