Bahar Ipek, Rachel A. Pollock, Craig Brown, Deniz Uner, Raul F. Lobo
We report H2 adsorption capacities reaching 0.05 mass% (wt. %) at 303 K and 1 atm H2 pressure on solid-state CuCl-exchanged [Al]-SSZ-13 and [B]-SSZ zeolites. Differential heat of H2 adsorption is found in the range between 16 KJ mol H2-1 and 48 KJ mol H2-1 on Cu(I)-SSZ-13 at 323 K and isosteric heat of adsorption is found between 20 kJ mol H2-1 and 55 kJ mol H6d2^-1 on Cu(I)-[B]-SSZ-13 at temperatures between 293 K and 323 K. Strong interactions between H2 and the copper cations in Cu(I)-SSZ-13 are evidenced using Rietveld refinements of Neutron Powder Diffraction patterns revealing Cu-deuterium (D2) distances of 2.3(1) angstrom} and 2.41(1) angstrom}. A temperature-dependent Cu(I) migration-away from the six-membered ring (6MR) and eight-membered ring (8MR)-is related to the high adsorption capacities of the samples at 303 K. At 10 K, access to Cu(I) at 6 MR is sterically hindered by framework oxygen atoms (Cu-Oframework distance of 2.196(5) angstrom}), rationalizing the low H2 adsorption capacities of Cu(I)-SSZ-13 samples as compared to Na-SSZ-13 at 77 K.
, Pollock, R.
, Brown, C.
, Uner, D.
and Lobo, R.
H<sub>2</sub> Adsorption on Cu(I)-SSZ-13, Journal of Physical Chemistry C, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=925088
(Accessed November 29, 2023)