Unconventional metal organic frameworks: porous cross-linked phosphonates
Unconventional metal organic frameworks: porous cross-linked phosphonates
复制标题
DOI：
10.1039/b807676f
复制
发表时间：
2008-01-01
影响因子：
4
通讯作者：
Clearfield, Abraham
中科院分区：
文献类型：
--
作者：
Clearfield, Abraham
在过去的十年中，金属有机骨架化合物（MOFs）呈指数增长。这些化合物的决定性特征是它们的多孔性。然而，在许多情况下，没有努力证明已经实现了稳定的多孔结构并且可以进入孔隙。在本文中，我们描述了最近的工作多孔柱撑锆二膦酸盐，和较新的和在许多方面不同的特点锡（IV）膦酸盐。Sn（IV）单膦酸盐形成表现出非常高的表面积的球形小球。表面积来自于它们的纳米尺寸的颗粒，这些颗粒以“纸牌屋”的方式排列。此外，它表明，1，4-单苯基二膦酸形成高度多孔（250-400米（2）克（-1））材料与锡（IV）时，在醇-水介质中制备。这与类似的Zr（IV）化合物的情况不同。芳基-和烷基二膦酸锆和锡柱的合成以及它们与间隔基如甲基-和单苯基膦酸的组合的许多变化已经产生了各种高度多孔的材料，其在空气中稳定至400 ° C，在酸性介质中高度稳定，当去溶剂化时不塌陷，并且可以在合成后和合成前改变以包括官能团。其他研究人员采取的几个新的方向也被描述。然而，在该演示中强调的是，交联的化合物形成快速沉淀成仅表现出短程有序的纳米颗粒的颗粒。因此，它们不同于更常规的M0 F，因为它们不适合于通过X射线或中子衍射技术的结构解决方案。相反，他们必须理解的基础上的建模和间接数据从EM，NMR，以及额外的光谱和纹理研究。
The past decade has witnessed an exponential growth of metal organic framework compounds (MOFs). The defining character of these compounds is their porosity. However, in many cases no effort was made to show evidence that a stable porous structure has been achieved and that the pores may be accessed. In the present paper we describe recent work on porous pillared zirconium diphosphonates, and the newer and in many respects different characteristics of tin(IV) phosphonates. The Sn(IV) monophosphonates form spherical globules that exhibit very high surface areas. The surface area arises from their nano-sized particles that pack in a "house of cards" arrangement. Also, it is shown that the 1,4-monophenyldiphosphonic acid forms highly porous (250-400 m(2) g(-1)) materials with Sn(IV) when prepared in alcohol-water media. This is not the case with analogous Zr(IV) compounds. The many variations in the syntheses of both the zirconium and tin aryl- and alkyldiphosphonate pillars and their combinations with spacers such as methyl- and monophenylphosphonic acid have created a variety of highly porous materials that are stable to 400 degrees C in air, highly stable in acid media, do not collapse when de-solvated, and can be post and presynthesis altered to include functional groups. Several new directions taken by other researchers are also described. However, it is emphasized in this presentation that the cross-linked compounds form particles that precipitate rapidly into nanoparticles that exhibit only short range order. Therefore, they differ from the more conventional MOFs in that they are not amenable to structure solution by X-ray or neutron diffraction techniques. Rather, they must be understood on the basis of modeling and indirect data from EM, NMR, and additional spectroscopic and textural studies.