Core-Shell Zeolitic Imidazolate Frameworks for Enhanced Hydrogen Storage
Core-Shell Zeolitic Imidazolate Frameworks for Enhanced Hydrogen Storage
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DOI：
10.1021/acsomega.7b01693
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发表时间：
2018-01-01
期刊：
影响因子：
4.1
通讯作者：
Singh, Sanjay K.
中科院分区：
文献类型：
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作者：
Panchariya, Dharmendra K.;Rai, Rohit K.;Singh, Sanjay K.
使用晶种介导的方法溶剂热合成核-壳ZIF-8@ZIF-67-和ZIF-67@ZIF 8-基沸石咪唑酯骨架（ZIF）。进行透射电子显微镜-能量色散X射线光谱法、线扫描、元素绘图、X射线光电子能谱法和电感耦合等离子体-原子发射光谱法分析，以确认两种核-壳ZIF的具有类似于0.50的受控Co/Zn元素组成的核-壳结构的形成。合成的核-壳ZIF-8@ZIF-67和ZIF-67@ZIF 8框架在77 K和1巴下赋予增强的H-2（2.03和1.69重量%）储存性能，其约为1.05重量%。41和18%，分别高于亲本ZIF-8。值得注意的是，由核-壳ZIF相对于Zn-Co/Zn-ZIF以及ZIF-8和ZIF-67的物理混合物显示的明显显著的H-2储存性质清楚地证明了它们独特的结构性质（孔隙度的限制）和由于表现优异的核-壳ZIF的核-壳形态而引起的元素异质性。H-2吸附等温线符合Langmuir模型（R-2 >= 0.9999）。沿着显著增强的H-2储存能力，核-壳ZIF还显示出改善的CO2捕获行为。因此，我们在这里证明，通过合理设计的多孔材料认可的控制结构特征可能会发现在H-2存储应用的高潜力。
Core-shell ZIF-8@ZIF-67- and ZIF-67@ZIF8-based zeolitic imidazolate frameworks (ZIFs) were synthesized solvothermally using a seed-mediated methodology. Transmission electron microscopy-energy-dispersive X-ray spectrometry, line scan, elemental mapping, X-ray photoelectron spectroscopy, and inductively coupled plasma-atomic emission spectroscopy analyses were performed to confirm the formation of a core-shell structure with the controlled Co/Zn elemental composition of similar to 0.50 for both the core-shell ZIFs. The synthesized core-shell ZIF-8@ZIF-67 and ZIF-67@ZIF8 frameworks conferred enhanced H-2 (2.03 and 1.69 wt %) storage properties at 77 K and 1 bar, which are ca. 41 and 18%, respectively, higher than that of the parent ZIF-8. Notably, the distinctly remarkable H-2 storage properties shown by both the core-shell ZIFs over the bimetallic Co/Zn-ZIF and the physical mixture of ZIF-8 and ZIF-67 clearly evidenced their unique structural properties (confinement of porosity) and elemental heterogeneity due to the core-shell morphology of the outperforming core-shell ZIFs. Moreover, H-2 adsorption isotherm data of these frameworks are best fitted with the Langmuir model (R-2 >= 0.9999). Along with the remarkably enhanced H-2 storage capacities, the core-shell ZIFs also displayed an improved CO2 capture behavior. Hence, we demonstrated here that the controlled structural features endorsed by the rationally designed porous materials may find high potential in H-2 storage applications.