当前位置: X-MOL 学术Energy Environ. Sci. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Balancing gravimetric and volumetric hydrogen density in MOFs
Energy & Environmental Science ( IF 32.5 ) Pub Date : 2017-10-11 00:00:00 , DOI: 10.1039/c7ee02477k
Alauddin Ahmed 1, 2, 3, 4 , Yiyang Liu 2, 3, 4, 5 , Justin Purewal 4, 6, 7, 8 , Ly D. Tran 2, 3, 4, 5 , Antek G. Wong-Foy 2, 3, 4, 5 , Mike Veenstra 4, 6, 7, 8 , Adam J. Matzger 2, 3, 4, 5 , Donald J. Siegel 1, 2, 3, 4, 9
Affiliation  

Metal organic frameworks (MOFs) are promising materials for the storage of hydrogen fuel due to their high surface areas, tunable properties, and reversible gas adsorption. Although several MOFs are known to exhibit high hydrogen densities on a gravimetric basis, realizing high volumetric capacities – a critical attribute for maximizing the driving range of fuel cell vehicles – remains a challenge. Here, MOFs that achieve high gravimetric and volumetric H2 densities simultaneously are identified computationally, and demonstrated experimentally. The hydrogen capacities of 5309 MOFs drawn from databases of known compounds were predicted using empirical (Chahine rule) correlations and direct atomistic simulations. A critical assessment of correlations between these methods, and with experimental data, identified pseudo-Feynman–Hibbs-based grand canonical Monte Carlo calculations as the most accurate predictive method. Based on these predictions, promising MOF candidates were synthesized and evaluated with respect to their usable H2 capacities. Several MOFs predicted to exhibit high capacities displayed low surface areas upon activation, highlighting the need to understand the factors that control stability. Consistent with the computational predictions, IRMOF-20 was experimentally demonstrated to exhibit an uncommon combination of high usable volumetric and gravimetric capacities. Importantly, the measured capacities exceed those of the benchmark compound MOF-5, the record-holder for combined volumetric/gravimetric performance. Our study illustrates the value of computational screening in pinpointing materials that optimize overall storage performance.

中文翻译:

平衡MOF中的重量氢和体积氢密度

金属有机骨架(MOF)由于具有高的表面积,可调节的特性和可逆的气体吸附性,因此是用于存储氢燃料的有前途的材料。尽管已知有几种MOF的重量密度较高,但实现高容积容量(最大化燃料电池汽车的续驶里程的关键属性)仍然是一个挑战。在这里,MOF可实现高重量和体积H 2密度可通过计算同时确定,并通过实验进行验证。使用经验(Chahine规则)相关性和直接原子模拟预测了从已知化合物的数据库中提取的5309个MOF的氢容量。对这些方法之间以及与实验数据之间的相关性进行的严格评估,将基于伪费恩曼–希伯斯的大正则经典蒙特卡洛计算确定为最准确的预测方法。根据这些预测,合成了有前景的MOF候选人,并对其可用的H 2进行了评估。能力。预计一些具有高容量的MOF会在激活时显示出较低的表面积,这突出表明需要了解控制稳定性的因素。与计算预测一致,IRMOF-20在实验上被证明具有高可用体积和重量分析能力的罕见组合。重要的是,测得的容量超过了基准化合物MOF-5(组合的体积/重量性能的记录保持者)的容量。我们的研究说明了精确筛选可优化整体存储性能的材料的计算筛选的价值。
更新日期:2017-10-23
down
wechat
bug