TY - JOUR
T1 - Coordination-chemistry control of proton conductivity in the iconic metal-organic framework material HKUST-1
AU - Jeong, Nak Cheon
AU - Samanta, Bappaditya
AU - Lee, Chang Yeon
AU - Farha, Omar K.
AU - Hupp, Joseph T.
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/1/11
Y1 - 2012/1/11
N2 - HKUST-1, a metal-organic framework (MOF) material containing Cu II-paddlewheel-type nodes and 1,3,5-benzenetricarboxylate struts, features accessible Cu II sites to which solvent or other desired molecules can be intentionally coordinated. As part of a broader investigation of ionic conductivity in MOFs, we unexpectedly observed substantial proton conductivity with the "as synthesized" version of this material following sorption of methanol. Although HKUST-1 is neutral, coordinated water molecules are rendered sufficiently acidic by Cu II to contribute protons to pore-filling methanol molecules and thereby enhance the alternating-current conductivity. At ambient temperature, the chemical identities of the node-coordinated and pore-filling molecules can be independently varied, thus enabling the proton conductivity to be reversibly modulated. The proton conductivity of HKUST-1 was observed to increase by ∼75-fold, for example, when node-coordinated acetonitrile molecules were replaced by water molecules. In contrast, the conductivity became almost immeasurably small when methanol was replaced by hexane as the pore-filling solvent.
AB - HKUST-1, a metal-organic framework (MOF) material containing Cu II-paddlewheel-type nodes and 1,3,5-benzenetricarboxylate struts, features accessible Cu II sites to which solvent or other desired molecules can be intentionally coordinated. As part of a broader investigation of ionic conductivity in MOFs, we unexpectedly observed substantial proton conductivity with the "as synthesized" version of this material following sorption of methanol. Although HKUST-1 is neutral, coordinated water molecules are rendered sufficiently acidic by Cu II to contribute protons to pore-filling methanol molecules and thereby enhance the alternating-current conductivity. At ambient temperature, the chemical identities of the node-coordinated and pore-filling molecules can be independently varied, thus enabling the proton conductivity to be reversibly modulated. The proton conductivity of HKUST-1 was observed to increase by ∼75-fold, for example, when node-coordinated acetonitrile molecules were replaced by water molecules. In contrast, the conductivity became almost immeasurably small when methanol was replaced by hexane as the pore-filling solvent.
UR - http://www.scopus.com/inward/record.url?scp=84862908717&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84862908717&partnerID=8YFLogxK
U2 - 10.1021/ja2110152
DO - 10.1021/ja2110152
M3 - Article
C2 - 22148287
AN - SCOPUS:84862908717
VL - 134
SP - 51
EP - 54
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 1
ER -