Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, TX 77843, USA.
Department of Chemistry, Texas A&M University, College Station, TX 77842-3012, USA.
Chemosphere. 2018 Oct;209:783-800. doi: 10.1016/j.chemosphere.2018.06.114. Epub 2018 Jun 18.
Heavy metals and radionuclides in water are a global environmental issue, which has been receiving considerable attention worldwide. Water-stable MOFs are green and recyclable materials to eliminate the environmental impacts caused by the hazardous heavy metal ions and radionuclides in water. This paper presents a systematical review on the current status of water-stable MOFs that capture and convert a wide range of heavy metal ions (e.g., As(III)/As(V), Pb(II), Hg(II), Cd(II), and Cr(III)/Cr(VI)) and radionuclides (e.g., U(VI), Se(IV)/Se(VI) and Cs(I)) in aqueous solution. Water-stable MOFs and MOF-based composites exhibit the superior adsorption capability for these metal species in water. Significantly, MOFs show high selectivity in capturing target metal ions even in the presence of multiple water constituents. Mechanisms involved in capturing metal ions are described. MOFs also have excellent catalytic performance (photocatalysis and catalytic reduction by formic acid) for Cr(VI) conversion to Cr(III). Future research is suggested to provide insightful guidance to enhance the performance of the MOFs in capturing target pollutants in aquatic environment.
水中的重金属和放射性核素是一个全球性的环境问题，已引起全球范围内的广泛关注。水稳定的 MOFs 是绿色且可回收的材料，可消除水中有害重金属离子和放射性核素所造成的环境影响。本文对水稳定的 MOFs 在水中捕获和转化各种重金属离子（例如 As(III)/As(V)、Pb(II)、Hg(II)、Cd(II)和 Cr(III)/Cr(VI))和放射性核素（例如 U(VI)、Se(IV)/Se(VI)和 Cs(I))的现状进行了系统综述。水稳定的 MOFs 和基于 MOF 的复合材料在水中对这些金属物种表现出优异的吸附能力。重要的是，MOFs 即使在存在多种水成分的情况下，也具有高选择性地捕获目标金属离子的能力。描述了捕获金属离子的机理。MOFs 还具有出色的催化性能（光催化和甲酸催化还原），可将 Cr(VI)转化为 Cr(III)。建议未来的研究提供有见地的指导，以提高 MOFs 在捕获水环境污染中目标污染物的性能。
