物理化学学报2018，Vol.34Issue(3)：286-295,10.DOI:10.3866/PKU.WHXB201708172
嵌入配位不饱和金属位对多孔芳香骨架材料储氢性能的影响
Effect of Coordinatively Unsaturated Metal Sites in Porous Aromatic Frameworks on Hydrogen Storage Capacity
摘要
Abstract
The effect of inserting coordinatively unsaturated metal sites (CUS) into porous aromatic frameworks (PAFs) on their hydrogen storage capacity was investigated systematically by density functional theory and grand canonical Monte Carlo simulations.The results indicate that the maximum excess gravimetric uptake of hydrogen possible with PAF-302MgO2_PBE100 is 7.97％ (w) at 77 K.The total uptakes of hydrogen by PAF-302 and PAF-303 functionalized with 100％ magnesium alkoxide at 77 K and 10 MPa were determined to be 9.9％ (w) (65.9 g·L-1) and 15.0％ (w) (50.5 g·L-1),respectively.These uptake values are 80％ (64.8％) and 173％ (26.3％),respectively,more than the gravimetric and volumetric targets set by the Department of Energy (DOE) of USA.They also exceed the targets set by NU-1101,presenting the highest measured performance of 9.9％ (w) (46.6 g·L-1) under the same conditions.Even at 243 K and 10 MPa,the total gravimetric and volumetric uptakes of hydrogen in the former are up to 5.13％ (w) and 34.19 g·L-1,which are about 93.3％ and 85.5％ of the targets set by DOE,respectively.By analyzing the isosteric heat of adsorption (Qst),radial distribution function,and mass center probability density,it is found that increasing the length of the organic linkers of PAFs incorporated with CUS will result in decreasing volumetric surface areas in spite of the increase in void fractions,which is the root of trade-offs between the total gravimetric and volumetric H2 uptake in porous materials.Additionally,CUS incorporation improves the affinity of PAF materials to H2 molecules,resulting in an enhancement of the volumetric hydrogen storage capacity.关键词
多孔芳香骨架材料/配位不饱和金属位/储氢/分子模拟/巨正则蒙特卡洛模拟Key words
Porous aromatic framework/CUS/Hydrogen storage/Molecular adsorption/GCMC simulation分类
化学化工引用本文复制引用
吴选军,李磊,彭亮,王叶彤,蔡卫权..嵌入配位不饱和金属位对多孔芳香骨架材料储氢性能的影响[J].物理化学学报,2018,34(3):286-295,10.基金项目
The project was supported by the National Natural Science Foundation of China (51272201,21476179),the China Scholarship Council for the Scholarship Support ([2016]3099),the Fundamental Research Funds for the Central Universities (175220002),and 2016 Wuhan Yellow Crane Talents (Science) Program.国家自然科学基金(51272201,21476179),国家留学基金委([2016]3099),中央高校基本科研业务费(175220002)和2016年武汉市黄鹤英才(科技)计划资助 （51272201,21476179）
