am6b06245_si_001.pdf (841.55 kB)
Tunable Gravimetric and Volumetric Hydrogen Storage Capacities in Polyhedral Oligomeric Silsesquioxane Frameworks
journal contribution
posted on 2016-09-07, 00:00 authored by Amol Deshmukh, Cheng-chau Chiu, Yun-Wen Chen, Jer-Lai KuoWe
study the hydrogen adsorption in porous frameworks composed
of silsesquioxane cages linked via boron substituted aromatic structures
by first-principles modeling. Such polyhedral oligomeric silsesquioxane
(POSS) frameworks can be further modified by decorating them with
metal atoms binding to the ring structures of the linkers. We have
considered Sc- and Ti-doped frameworks which bind H2 via
so-called Kubas interaction between hydrogen molecules and transition
metal atoms. It will be demonstrated that the maximum H2 gravimetric capacity can be improved to more than 7.5 wt % by using
longer linkers with more ring structures. However, the maximum H2 volumetric capacity can be tuned to more than 70 g/L by varying
the size of silsesquioxane cages. We are optimistic that by varying
the building blocks, POSS frameworks can be modified to meet the targets
for the gravimetric and volumetric capacities set by the U.S. Department
of Energy.