Controlled Manipulation of Metal-Organic Framework Layers to Nanometer Precision Inside Large Mesochannels of Ordered Mesoporous Silica for Enhanced Removal of Bisphenol A from Water
Controlled Manipulation of Metal-Organic Framework Layers to Nanometer Precision Inside Large Mesochannels of Ordered Mesoporous Silica for Enhanced Removal of Bisphenol A from Water
复制标题
在有序介孔二氧化硅大介孔内对金属有机框架层进行纳米级精度的受控操作，以增强从水中去除双酚 A
DOI：
10.1021/acsami.8b17508
复制
发表时间：
2019-01-30
影响因子：
9.5
通讯作者：
Chen, Jiping
中科院分区：
文献类型：
--
作者：
Peng, Junyu;Li, Yun;Chen, Jiping
分层多孔金属有机骨架（MOF）复合材料的设计不仅提高了材料的性能，而且拓宽了其应用领域，受到了广泛的关注。到目前为止，由于在有限空间中生长MOF的困难，在保持其各自固有特性的同时，在有序的介沟道中控制纳米厚MOF层仍然是一个主要挑战。本文采用分步配位的方法，以大介孔SBA-15为材料，形成了壁厚（通道壁和涂层）达8.0 nm、开孔尺寸达7.7 nm的层次化微介孔杂化材料，并通过调节咪唑酸分子筛骨架-8 （ZIF-8）涂层的生长周期，实现了具有纳米精度的壁厚控制。与纯ZIF-8相比，ZIF-8@SBA-15复合材料对水中双酚A的吸附量提高了2倍以上，吸附速率常数提高了约20倍，这可能是由于ZIF-8的高吸附能力和SBA-15的快速扩散特性的协同作用。更重要的是，降解的ZIF-8@SBA-15复合材料可以通过简单的浸泡在2-甲基咪唑溶液中完全恢复。易于恢复和良好的可重复使用性进一步使ZIF-8@SBA-15成为有效去除水中有机污染物的有前途的吸附剂。
Considerable attention has been paid on the design of hierarchical porous metal organic framework (MOF) composites, which not only enhances the performance but also broadens the applications of MOFs. So far, controlled manipulation of nanometer-thick MOF layers in ordered mesochannels, while retaining their respective intrinsic properties, is still a main challenge because of the difficulty of growing MOFs in confined space. Herein, using a step-by-step coordination method, the formation of a hierarchical micro-mesoporous hybrid with a wall (channel wall and coating layer) thickness of up to 8.0 nm and open pore size down to 7.7 nm has been achieved based on large mesoporous SBA-15, and the wall thickness with nanometer precision can be controlled by adjusting the growth cycles of zeolite imidazolate framework-8 (ZIF-8) coating layers. Compared to pure ZIF-8, the obtained ZIF-8@SBA-15 composites showed more than 2-fold enhancement in adsorption capacity and approximately 20-fold improvement in the adsorption rate constant for bisphenol A in water, which could be ascribed to the synergistic effects of the high adsorption ability from ZIF-8 and the fast diffusion property from SBA-15. More importantly, the degraded ZIF-8@SBA-15 composite can be completely restored by a simple immersion into 2-methylimidazole solution. The easy restorability and good reusability further enable ZIF-8@SBA-15 as a promising adsorbent for effectively removing organic contaminants from water.