Thornton Aaron W, Nairn Kate M, Hill James M, Hill Anita J, Hill Matthew R
CSIRO Materials Science and Engineering, Private Bag 33, Clayton South MDC, Victoria 3169, Australia.
J Am Chem Soc. 2009 Aug 5;131(30):10662-9. doi: 10.1021/ja9036302.
A new concept is described for methane and hydrogen storage materials involving the incorporation of magnesium-decorated fullerenes within metal-organic frameworks (MOFs). The system is modeled using a novel approach underpinned by surface potential energies developed from Lennard-Jones parameters. Impregnation of MOF pores with magnesium-decorated Mg(10)C(60) fullerenes, denoted as Mg-C(60)@MOF, places exposed metal sites with high heats of gas adsorption into intimate contact with large surface area MOF structures. Perhaps surprisingly, given the void space occupied by C(60), this impregnation delivers remarkable gas uptake, according to our modeling, which predicts exceptional performance for the Mg-C(60)@MOF family of materials. These predictions include a volumetric methane uptake of 265 v/v, the highest reported value for any material, which significantly exceeds the U.S. Department of Energy target of 180 v/v. We also predict a very high hydrogen adsorption enthalpy of 11 kJ mol(-1) with relatively little decrease as a function of H(2) filling. This value is close to the calculated optimum value of 15.1 kJ mol(-1) and is achieved concurrently with saturation hydrogen uptake in large amounts at pressures under 10 atm.
本文描述了一种用于甲烷和氢气存储材料的新概念，该概念涉及将镁修饰的富勒烯掺入金属有机框架（MOF）中。该系统采用一种新方法进行建模，该方法以基于 Lennard-Jones 参数开发的表面势能为基础。用镁修饰的 Mg(10)C(60) 富勒烯（表示为 Mg-C(60)@MOF）浸渍 MOF 孔，使具有高气体吸附热的暴露金属位点与大表面积的 MOF 结构紧密接触。根据我们的模型，考虑到 C(60) 占据的空隙空间，这种浸渍能实现显著的气体吸收，这预测了 Mg-C(60)@MOF 材料家族具有卓越的性能。这些预测包括体积甲烷吸收率为 265 v/v，这是任何材料报道的最高值，大大超过了美国能源部 180 v/v 的目标。我们还预测，在 H(2) 填充时，氢气吸附焓非常高，为 11 kJ mol(-1)，且随 H(2) 填充量的减少相对较小。该值接近计算得出的最佳值 15.1 kJ mol(-1)，并且在低于 10 atm 的压力下大量氢气饱和吸收时同时实现。
