{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T16:22:11Z","timestamp":1788366131028,"version":"build-2803163510"},"reference-count":46,"publisher":"American Chemical Society (ACS)","issue":"30","license":[{"start":{"date-parts":[[2018,7,18]],"date-time":"2018-07-18T00:00:00Z","timestamp":1531872000000},"content-version":"vor","delay-in-days":43,"URL":"https:\/\/pubs.acs.org\/page\/policy\/authorchoice_termsofuse.html"}],"funder":[{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy","doi-asserted-by":"publisher","award":["DE-FG02-08ER15967"],"award-info":[{"award-number":["DE-FG02-08ER15967"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000078","name":"Division of Materials Research","doi-asserted-by":"publisher","award":["1648815"],"award-info":[{"award-number":["1648815"]}],"id":[{"id":"10.13039\/100000078","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007059","name":"Northwestern University","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/100007059","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004919","name":"King Abdulaziz City for Science and Technology","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/501100004919","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/na","name":"Joint Center of Excellence in Integrated NanoSystems","doi-asserted-by":"publisher","award":["34-948"],"award-info":[{"award-number":["34-948"]}],"id":[{"id":"10.13039\/na","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2018,8,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Exactly 50 years ago, the ground-breaking discovery of dibenzo[18]crown-6 (DB18C6) by Charles Pedersen led to the use of DB18C6 as a receptor in supramolecular chemistry and a host in host\u2013guest chemistry. We have demonstrated proton conductivity in Tro\u0308ger\u2019s base-linked polymers through hydrogen-bonded networks formed from adsorbed water molecules on the oxygen atoms of DB18C6 under humid conditions. Tro\u0308ger\u2019s base-linked polymers\u2500poly(TBL-DB18C6)-t and poly(TBL-DB18C6)-c\u2500synthesized by the in situ alkylation and cyclization of either trans- or cis-di(aminobenzo) [18]crown-6 at room temperature have been isolated as high-molecular-weight polymers. The macromolecular structures of the isomeric poly(TBL-DB18C6)s have been established by spectroscopic techniques and size-exclusion chromatography. The excellent solubility of these polymers in chloroform allows the formation of freestanding membranes, which are thermally stable and also show stability under aqueous conditions. The hydrophilic nature of the DB18C6 building blocks in the polymer facilitates retention of water as confirmed by water vapor adsorption isotherms, which show a 23 wt % water uptake. The adsorbed water is retained even after reducing the relative humidity to 25%. The proton conductivity of poly(TBL-DB18C6)-t, which is found to be 1.4 \u00d7 10\u20134 mS cm\u20131 in a humid environment, arises from the hydrogen bonding and the associated proton-hopping mechanism, as supported by a modeling study. In addition to proton conductivity, the Tro\u0308ger\u2019s base-linked polymers reported here promise a wide range of applications where the sub-nanometer-sized cavities of the crown ethers and the robust film-forming ability are the governing factors in dictating their properties.<\/jats:p>","DOI":"10.1021\/acsami.8b05532","type":"journal-article","created":{"date-parts":[[2018,6,5]],"date-time":"2018-06-05T05:24:18Z","timestamp":1528176258000},"page":"25303-25310","source":"Crossref","is-referenced-by-count":40,"title":["Proton\nConduction in Tro\u0308ger\u2019s Base-Linked Poly(crown ether)s"],"prefix":"10.1021","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4968-6686","authenticated-orcid":true,"given":"Hasmukh A.","family":"Patel","sequence":"first","affiliation":[{"name":"Northwestern University , , 2145 Sheridan Road , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Selberg","sequence":"additional","affiliation":[{"name":"University of California Santa Cruz , , , ,","place":["Santa Cruz, California, United States, 95064"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dhafer","family":"Salah","sequence":"additional","affiliation":[{"name":"King Abdulaziz City for Science and Technology (KACST) , ,","place":["Riyadh, Saudi Arabia, 11442"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8634-4028","authenticated-orcid":true,"given":"Haoyuan","family":"Chen","sequence":"additional","affiliation":[{"name":"Northwestern University , , 2145 Sheridan Road , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yijun","family":"Liao","sequence":"additional","affiliation":[{"name":"Northwestern University , , 2145 Sheridan Road , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6955-3285","authenticated-orcid":true,"given":"Siva Krishna","family":"Mohan Nalluri","sequence":"additional","affiliation":[{"name":"Northwestern University , , 2145 Sheridan Road , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9904-9845","authenticated-orcid":true,"given":"Omar K.","family":"Farha","sequence":"additional","affiliation":[{"name":"Northwestern University , , 2145 Sheridan Road , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2925-9246","authenticated-orcid":true,"given":"Randall Q.","family":"Snurr","sequence":"additional","affiliation":[{"name":"Northwestern University , , 2145 Sheridan Road , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7898-2479","authenticated-orcid":true,"given":"Marco","family":"Rolandi","sequence":"additional","affiliation":[{"name":"University of California Santa Cruz , , , ,","place":["Santa Cruz, California, United States, 95064"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3161-3697","authenticated-orcid":true,"given":"J. Fraser","family":"Stoddart","sequence":"additional","affiliation":[{"name":"Northwestern University , , 2145 Sheridan Road , , ,","place":["Evanston, Illinois, United States, 60208"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2018,6,5]]},"reference":[{"key":"2026090212093063100_cit1","doi-asserted-by":"publisher","first-page":"11586","DOI":"10.1002\/anie.201101891","article-title":"Development and\nevaluation of porous materials for carbon dioxide separation and capture","volume":"50","author":"Bae","year":"2011","journal-title":"Angew. Chem., Int. 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Sci."},{"key":"2026090212093063100_cit30","doi-asserted-by":"publisher","first-page":"12981","DOI":"10.1038\/ncomms12981","article-title":"Electronic control of H+ current\nin a bioprotonic device with Gramicidin A and Alamethicin","volume":"7","author":"Hemmatian","year":"2016","journal-title":"Nat. Commun."},{"key":"2026090212093063100_cit31","doi-asserted-by":"publisher","first-page":"6252","DOI":"10.1016\/j.tet.2008.04.111","article-title":"Functionalized\nanalogues of Tro\u0308ger\u2019s base: scope and limitations of\na general synthetic procedure and facile, predictable method for the\nseparation of enantiomers","volume":"64","author":"Didier","year":"2008","journal-title":"Tetrahedron"},{"key":"2026090212093063100_cit32","doi-asserted-by":"publisher","first-page":"225","DOI":"10.1002\/prac.18870360123","article-title":"Ueber einige mittelst nascirenden\nformaldehydes entstehende basen","volume":"36","author":"Tro\u0308ger","year":"1987","journal-title":"J. Prakt. 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Soc."},{"key":"2026090212093063100_cit42","doi-asserted-by":"publisher","DOI":"10.1126\/sciadv.1600112","article-title":"Proton conductivity in ampullae of\nLorenzini jelly","volume":"2","author":"Josberger","year":"2016","journal-title":"Sci. Adv."},{"key":"2026090212093063100_cit43","doi-asserted-by":"publisher","first-page":"436","DOI":"10.1021\/cm502939r","article-title":"Protonic and electronic transport\nin hydrated thin films of the pigment eumelanin","volume":"27","author":"Wu\u0308nsche","year":"2015","journal-title":"Chem. Mater."},{"key":"2026090212093063100_cit44","doi-asserted-by":"publisher","first-page":"2481","DOI":"10.1038\/srep02481","article-title":"H+-type and OH\u2013-type biological\nprotonic semiconductors and complementary devices","volume":"3","author":"Deng","year":"2013","journal-title":"Sci. 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Chem."}],"container-title":["ACS Applied Materials &amp; Interfaces"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/acsami.8b05532","content-type":"application\/pdf","content-version":"vor","intended-application":"unspecified"},{"URL":"https:\/\/pubs.acs.org\/aamick\/article-pdf\/10\/30\/25303\/66926389\/acsami.8b05532.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.acs.org\/aamick\/article-pdf\/10\/30\/25303\/66926389\/acsami.8b05532.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T16:09:39Z","timestamp":1788365379000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/aamick\/article\/10\/30\/25303\/708942\/Proton-Conduction-in-Tro-ger-s-Base-Linked-Poly"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,6,5]]},"references-count":46,"journal-issue":{"issue":"30","published-online":{"date-parts":[[2018,6,5]]},"published-print":{"date-parts":[[2018,8,1]]}},"URL":"https:\/\/doi.org\/10.1021\/acsami.8b05532","relation":{},"ISSN":["1944-8244","1944-8252"],"issn-type":[{"value":"1944-8244","type":"print"},{"value":"1944-8252","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,6,5]]}}}