Aggarwal Himanshu, Das Raj Kumar, Bhatt Prashant M, Barbour Leonard J
Department of Chemistry and Polymer Science , University of Stellenbosch , Matieland 7602 , Stellenbosch , South Africa . Email:
Chem Sci. 2015 Aug 1;6(8):4986-4992. doi: 10.1039/c5sc01796c. Epub 2015 Jun 11.
A known pillared layered metal-organic framework [Co(ndc)(bpy)] is shown to undergo a change in degree of interpenetration from a highly porous doubly-interpenetrated framework () to a less porous triply-interpenetrated framework (). The transformation involves an intermediate empty doubly-interpenetrated phase () which has been isolated for the first time for this kind of phenomenon by altering the conditions of activation of the as-synthesized material. Interestingly, all the transformations occur in single-crystal to single-crystal fashion. Changes in degree of interpenetration have not been explored much to date and their implications with regard to the porosity of MOFs still remain largely unknown. The present study not only provides a better understanding of such dramatic structural changes in MOF materials, but also describes an original way of controlling interpenetration by carefully optimizing the temperature of activation. In addition to studying the structural mechanism of conversion from to , sorption analysis has been carried out on both the intermediate () and the triply-interpenetrated () forms to further explain the effect that switching of interpenetration mode has on the porosity of the MOF material.
一种已知的柱状层状金属有机框架[Co(ndc)(bpy)]被证明会发生互穿程度的变化，从高度多孔的双互穿框架（）转变为孔隙率较低的三互穿框架（）。这种转变涉及一个中间的空双互穿相（），通过改变合成材料的活化条件，首次分离出了这种现象的此类中间相。有趣的是，所有转变均以单晶到单晶的方式发生。迄今为止，互穿程度的变化尚未得到充分探索，其对金属有机框架孔隙率的影响在很大程度上仍然未知。本研究不仅能更好地理解金属有机框架材料中如此显著的结构变化，还描述了一种通过仔细优化活化温度来控制互穿的原始方法。除了研究从到的转变结构机制外，还对中间相（）和三互穿相（）形式进行了吸附分析，以进一步解释互穿模式转变对金属有机框架材料孔隙率的影响。
