Department of Chemistry, University of California , Berkeley, California 94720, United States.
J Am Chem Soc. 2014 Feb 12;136(6):2432-40. doi: 10.1021/ja4105478. Epub 2014 Feb 4.
The elimination of specific environmental and industrial contaminants, which are hazardous at only part per million to part per billion concentrations, poses a significant technological challenge. Adsorptive materials designed for such processes must be engendered with an exceptionally high enthalpy of adsorption for the analyte of interest. Rather than relying on a single strong interaction, the use of multiple chemical interactions is an emerging strategy for achieving this requisite physical parameter. Herein, we describe an efficient, catalytic synthesis of diamondoid porous organic polymers densely functionalized with carboxylic acids. Physical parameters such as pore size distribution, application of these materials to low-pressure ammonia adsorption, and comparison with analogous materials featuring functional groups of varying acidity are presented. In particular, BPP-5, which features a multiply interpenetrated structure dominated by <6 Å pores, is shown to exhibit an uptake of 17.7 mmol/g at 1 bar, the highest capacity yet demonstrated for a readily recyclable material. A complementary framework, BPP-7, features slightly larger pore sizes, and the resulting improvement in uptake kinetics allows for efficient adsorption at low pressure (3.15 mmol/g at 480 ppm). Overall, the data strongly suggest that the spatial arrangement of acidic sites allows for cooperative behavior, which leads to enhanced NH3 adsorption.
消除特定的环境和工业污染物，这些污染物在百万分之一到十亿分之一的浓度下是危险的，这是一个重大的技术挑战。为此类工艺设计的吸附材料必须对感兴趣的分析物具有极高的吸附焓。除了依赖单一的强相互作用外，使用多种化学相互作用是实现这一必要物理参数的新兴策略。在此，我们描述了一种高效、催化合成的具有羧酸官能团的类金刚石多孔有机聚合物。介绍了物理参数，如孔径分布、这些材料在低压氨吸附中的应用以及与具有不同酸度官能团的类似材料的比较。特别是，BPP-5 具有由 <6 Å 孔主导的多重互穿结构，在 1 巴时表现出 17.7 mmol/g 的吸收量，这是迄今为止可回收材料中展示的最高容量。一个互补的框架，BPP-7，具有稍大的孔径，由此产生的吸收动力学的改善允许在低压下进行有效的吸附（在 480 ppm 时为 3.15 mmol/g）。总的来说，这些数据强烈表明，酸性位的空间排列允许协同作用，从而导致增强的 NH3 吸附。
