Strong CO2 Binding in a Water-Stable, Triazolate-Bridged Metal-Organic Framework Functionalized with Ethylenediamine
Strong CO2 Binding in a Water-Stable, Triazolate-Bridged Metal-Organic Framework Functionalized with Ethylenediamine
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DOI：
10.1021/ja903411w
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发表时间：
2009-07-01
影响因子：
15
通讯作者：
Long, Jeffrey R.
中科院分区：
文献类型：
--
作者：
Demessence, Aude;D'Alessandro, Deanna M.;Long, Jeffrey R.
CuCl 2中心点2 H（2）O与1，3，5-三（1H-1，2，3-三唑-5-基）苯（H（3）BTTri）在DMF中于100 ℃反应生成金属有机骨架H-3[（Cu 4Cl）（3）（BTTri）（8）（DMF）（12）]中心点7 DMF中心点76 H（2）O（1-DMF）。方钠石型骨架结构由BTTri（3-）-连接的[Cu 4Cl]（7+）正方形簇组成，其中每个Cu-II中心具有指向大孔内部的末端DMF配体。该框架具有高达270摄氏度的高热稳定性，以及在空气、沸水和酸性介质中的优异化学稳定性。将客体溶剂和结合的DMF分子交换为甲醇以得到1-MeOH后，在180 ° C下骨架的完全去溶剂化产生在其表面上具有暴露的Cu-II位点的H-3[（Cu 4Cl）（3）（BTTri）（8）]（1）。根据先前报道的方案，乙二胺分子接枝到这些位点上，得到1-烯，具有末端烷基胺基团。N-2吸附等温线表明接枝后BET表面积从1770 m2/g降低到345 m2/g。1在77 K下的H-2吸附数据表明在1.2巴下完全可逆的吸收为1.2重量%，而195 K下的CO2等温线显示在1巴下的最大吸收为90重量%。与1相比，烷基胺官能化的骨架I-en在298 K和高达约100 K的压力下表现出更高的CO2吸收。0.1 bar，以及在所有测量的压力下更高的CO2/N-2选择性。值得注意的是，1-烯还表现出90 kJ/mol的CO2吸附的电子等排热，这远高于1所观察到的21 kJ/mol。这种化学吸附相互作用是迄今为止报道的最强的金属-有机框架，并指出了烷基胺附加的框架用于从低压烟道气流中燃烧后捕获CO2的潜在效用。
Reaction of CuCl2 center dot 2H(2)O with 1,3,5-tris(1H-1,2,3-triazol-5-yl)benzene (H(3)BTTri) in DMF at 100 degrees C generates the metal-organic framework H-3[(Cu4Cl)(3)(BTTri)(8)(DMF)(12)]center dot 7DMF center dot 76H(2)O (1-DMF). The sodalite-type structure of the framework consists of BTTri(3-)-linked [Cu4Cl](7+) square clusters in which each Cu-II center has a terminal DMF Ligand directed toward the interior of a large pore. The framework exhibits a high thermal stability of up to 270 degrees C, as well as exceptional chemical stability in air, boiling water, and acidic media. Following exchange of the guest solvent and bound DMF molecules for methanol to give 1-MeOH, complete desolvation of the framework at 180 degrees C generated H-3[(Cu4Cl)(3)(BTTri)(8)] (1) with exposed Cu-II sites on its surface. Following a previously reported protocol, ethylenediamine molecules were grafted onto these sites to afford 1-en, featuring terminal alkylamine groups. The N-2 adsorption isotherms indicate a reduction in the BET surface area from 1770 to 345 m(2)/g following grafting. The H-2 adsorption data at 77 K for 1 indicate a fully reversible uptake of 1.2 wt % at 1.2 bar, while the CO2 isotherm at 195 K shows a maximal uptake of 90 wt % at 1 bar. Compared to 1, the alkylamine-functionalized framework I-en exhibits a higher uptake of CO2 at 298 K and pressures up to ca. 0.1 bar, as well as a higher CO2/N-2 selectivity at all measured pressures. Significantly, 1-en also exhibits an isosteric heat of CO2 adsorption of 90 kJ/mol, which is much higher than the 21 kJ/mol observed for 1. This chemisorption interaction is the strongest reported to date for a metal-organic framework and points toward the potential utility of alkylamine-appended frameworks for the postcombustion capture of CO2 from low-pressure flue gas streams.