A comparative investigation of H-2 adsorption strength in Cd- and Zn-based metal organic framework-5
2008 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 129, no 16Article in journal (Refereed) Published
Hydrogen binding energies for the primary and secondary adsorption sites in the Cd- and Zn-based metal organic framework-5 (MOF-5) were studied using density functional theory. Out of the three exchange-correlation functionals employed in our study, we find that the local density approximation yields a qualitatively correct description of the interaction strengths of H-2 in MOF-5 systems. The H-2 adsorption energies for all trapping sites in Zn- and Cd-based MOF-5 are seen to be of the same order of magnitude but with a generally stronger binding in Cd- based MOF-5 as compared to Zn- based MOF-5. In particular, the H-2 binding energy at the secondary adsorption sites in Cd- based MOF-5 is increased by around 25% compared to Zn-based MOF-5. This result suggests that Cd- based MOF-5 would be better suited to store hydrogen at higher temperatures than Zn-based MOF-5.
Place, publisher, year, edition, pages
2008. Vol. 129, no 16
density-functional theory, hydrogen adsorption, correlation-energy, electron-gas, storage, accurate, binding, forces, design, mofs
IdentifiersURN: urn:nbn:se:kth:diva-17934DOI: 10.1063/1.2997377ISI: 000260572300007ScopusID: 2-s2.0-55349095434OAI: oai:DiVA.org:kth-17934DiVA: diva2:335979
QC 201005252010-08-052010-08-05Bibliographically approved