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In this paper, nanoscale zero-valent iron (NZVI), which has great potential in environmental purification is introduced. However, NZVI is easy to accumulate and oxidize, which limits its ability to remove pollutants. Hence several modified NZVI are proposed to overcome its shortcomings in this paper. The heavy metal ions, radionuclides and organic pollutants in the environment are removal by NZVI based materials, and their removal behaviors had been analyzed. This paper also reviews the factors affecting the removal of pollutants by NZVI-based materials, such as pH, ionic strength, contact time, reaction temperature, interfering ions and humic acids. In addition, it is also introduced that NZVI is toxic in the environment, and it also can be recovered and has different removal effects in different water environment. In short, this paper gives a comprehensive summary of NZVI, including its modification methods, pollutants removal, influencing factors of pollutants removal and implication to environment. It provides a strong theoretical basis for the future development of NZVI based materials. [Display omitted] • The characteristics of NZVI-based materials are briefly introduced and summarized. • The removal mechanisms of different pollutants are highlighted. • The influence factors and environmental implications are analyzed. • Future researches of NZVI-based materials in water remediation are discussed. [ABSTRACT FROM AUTHOR]

• The synthesis strategies of ZIFs are briefly introduced and summarized. • Batch experiment, spectral analysis and DFT are used to explore mechanisms. • The mechanisms mainly ascribe to coordination and electrostatic interaction. • Large SSA and sufficient functional groups endow ZIFs excellent performance. • Multi-factor influences demonstrate the practical application potential of ZIFs. With the rapid economic globalization and energy development, heavy metal ions/radionuclides are inevitably discharged into aqueous system and cause pollution, which seriously endanger human health and environmental sustainability. In recent years, zeolitic imidazolate frameworks (ZIFs) with huge specific surface area, excellent pore structure and abundant surface functional groups show great potential in the elimination of heavy metal ions/radionuclides. This review systematically summarizes the research progress of ZIFs and ZIF-based materials for capturing heavy metal ions/radionuclides. Firstly, the preparation and modification of ZIF-based materials are briefly introduced. Then, the removal behaviors and possible interaction mechanisms between ZIF-based materials and pollutants are explored through macro-batch experiments, micro-spectroscopy analyses and theoretical calculations. In addition, the partition coefficient as evaluation indicator was employed to objectively compare the removal performance of ZIFs and other commonly used traditional adsorbents for heavy metal ions/radionuclides. Finally, the challenges and prospects of ZIF materials in environmental governance are briefly discussed so as to provide references for future research and practical applications. [ABSTRACT FROM AUTHOR]