Chiu, Nan ChiehCompton, DaltonGładysiak, AndrzejSimrod, ScottKhivantsev, KonstantinWoo, Tom K.Stadie, Nicholas P.Stylianou, Kyriakos C.2024-03-012024-03-012023-11Nan Chieh Chiu, Dalton Compton, Andrzej Gładysiak, Scott Simrod, Konstantin Khivantsev, Tom K. Woo, Nicholas P. Stadie, and Kyriakos C. Stylianou ACS Applied Materials & Interfaces 2023 15 (45), 52788-52794 DOI: 10.1021/acsami.3c121391944-8252https://scholarworks.montana.edu/handle/1/18346Copyright American Chemical Society 2023In this study, we utilized an ultramicroporous metal–organic framework (MOF) named [Ni3(pzdc)2(ade)2(H2O)4]·2.18H2O (where H3pzdc represents pyrazole-3,5-dicarboxylic acid and ade represents adenine) for hydrogen (H2) adsorption. Upon activation, [Ni3(pzdc)2(ade)2] was obtained, and in situ carbon monoxide loading by transmission infrared spectroscopy revealed the generation of open Ni(II) sites. The MOF displayed a Brunauer–Emmett–Teller (BET) surface area of 160 m2/g and a pore size of 0.67 nm. Hydrogen adsorption measurements conducted on this MOF at 77 K showed a steep increase in uptake (up to 1.93 mmol/g at 0.04 bar) at low pressure, reaching a H2 uptake saturation at 2.11 mmol/g at ∼0.15 bar. The affinity of this MOF for H2 was determined to be 9.7 ± 1.0 kJ/mol. In situ H2 loading experiments supported by molecular simulations confirmed that H2 does not bind to the open Ni(II) sites of [Ni3(pzdc)2(ade)2], and the high affinity of the MOF for H2 is attributed to the interplay of pore size, shape, and functionality.en-USCopyright American Chemical Society 2023https://pubs.acs.org/page/rightslinkno.jspmetal−organic frameworksultramicroporeshydrogen uptakehydrogen-absorbent interactionssilent open metal sitesArticle