ACS Appl Mater Interfaces. 2019 Nov 27;11(47):44751-44757. doi: 10.1021/acsami.9b16423. Epub 2019 Nov 18.
By adjusting the stretch state of a triethylenetetramine (TETA) chain in an amine-functionalized porous organic polymer (POP), two adsorbents were designed to study the rational microenvironment for heavy metal ion removal. The quantum calculation elucidated that the hooped amino chains in FC-POP-CHTETA-H exhibited stronger interactions with Pb(II) than the extended one in FC-POP-CHTETA-E, not only through metal-ligand chelation but also metal coordination. The high binding energy of -2624 kJ mol as well as the constructed microenvironment by the hooped amino chains ensured an extremely high Pb(II) capacity of 1134 mg g on FC-POP-CHTETA-H. Meanwhile, no more than 5 min to approach adsorption equilibrium revealed its ultrafast adsorption rate. It also showed excellent broad removal capability for multiple metal ions and nonsensitivity to pH. Therefore, by controlling the microenvironmental structures with suitable porosity, functional group stretching states, and coordination modes, the removal efficiency of heavy metal ions would be significantly enhanced, which further provided a promising strategy for designing a rational microenvironment to improve the task-specific separation properties.
通过调节三乙烯四胺（TETA）链在胺功能化多孔有机聚合物（POP）中的拉伸状态，设计了两种吸附剂来研究重金属离子去除的合理微环境。量子计算阐明，在 FC-POP-CHTETA-H 中，环化的氨基链与 Pb(II) 之间的相互作用比伸展的氨基链强，这不仅是通过金属配体螯合，还通过金属配位。高结合能-2624 kJ mol 以及由环化的氨基链构建的微环境确保了在 FC-POP-CHTETA-H 上具有极高的 Pb(II) 容量 1134 mg g。同时，吸附平衡的达到时间不超过 5 分钟，表明其具有超快的吸附速率。它还表现出对多种金属离子的优异的广谱去除能力，并且对 pH 值不敏感。因此，通过控制具有合适的孔隙率、官能团拉伸状态和配位模式的微环境结构，可以显著提高重金属离子的去除效率，这进一步为设计合理的微环境以提高特定任务的分离性能提供了有前途的策略。
