{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T20:12:51Z","timestamp":1779221571344,"version":"3.51.4"},"reference-count":78,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2015,11,13]],"date-time":"2015-11-13T00:00:00Z","timestamp":1447372800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["MO 1060\/19-1"],"award-info":[{"award-number":["MO 1060\/19-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["Si609\/14-1"],"award-info":[{"award-number":["Si609\/14-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007210","name":"RWTH Aachen University","doi-asserted-by":"publisher","award":["ACA"],"award-info":[{"award-number":["ACA"]}],"id":[{"id":"10.13039\/501100007210","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Zeolites have been found to be promising sensor materials for a variety of gas molecules such as NH3, NOx, hydrocarbons, etc. The sensing effect results from the interaction of the adsorbed gas molecules with mobile cations, which are non-covalently bound to the zeolite lattice. The mobility of the cations can be accessed by electrical  low-frequency (LF; mHz to MHz) and high-frequency (HF; GHz) impedance measurements. Recent developments allow in situ monitoring of catalytic reactions on proton-conducting zeolites used as catalysts. The combination of such in situ impedance measurements with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), which was applied to monitor the selective catalytic reduction of nitrogen oxides (DeNOx-SCR), not only improves our understanding of the sensing properties of zeolite catalysts from integral electric signal to molecular processes, but also bridges the length scales being studied, from centimeters to nanometers. In this work, recent developments of zeolite-based, impedimetric sensors for automotive exhaust gases, in particular NH3, are summarized. The electrical response to NH3 obtained from LF impedance measurements will be compared with that from HF impedance measurements, and correlated with the infrared spectroscopic characteristics obtained from the DRIFTS studies of molecules involved in the catalytic conversion. The future perspectives, which arise from the combination of these methods, will be discussed.<\/jats:p>","DOI":"10.3390\/s151128915","type":"journal-article","created":{"date-parts":[[2015,11,16]],"date-time":"2015-11-16T05:40:47Z","timestamp":1447652447000},"page":"28915-28941","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Correlating the Integral Sensing Properties of Zeolites with Molecular Processes by Combining Broadband Impedance and DRIFT Spectroscopy\u2014A New Approach for Bridging the Scales"],"prefix":"10.3390","volume":"15","author":[{"given":"Peirong","family":"Chen","sequence":"first","affiliation":[{"name":"Institute of Inorganic Chemistry (IAC) and Center for Automotive Catalytic Systems Aachen (ACA), RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simon","family":"Sch\u00f6nebaum","sequence":"additional","affiliation":[{"name":"Institute of Inorganic Chemistry (IAC) and Center for Automotive Catalytic Systems Aachen (ACA), RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thomas","family":"Simons","sequence":"additional","affiliation":[{"name":"Institute of Inorganic Chemistry (IAC) and Center for Automotive Catalytic Systems Aachen (ACA), RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6960-9805","authenticated-orcid":false,"given":"Dieter","family":"Rauch","sequence":"additional","affiliation":[{"name":"Department of Functional Materials, Bayreuth Engine Research Center (BERC) and Zentrum f\u00fcr Energietechnik (ZET), University of Bayreuth, Universit\u00e4tsstra\u00dfe 30, 95440 Bayreuth, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6960-9805","authenticated-orcid":false,"given":"Markus","family":"Dietrich","sequence":"additional","affiliation":[{"name":"Department of Functional Materials, Bayreuth Engine Research Center (BERC) and Zentrum f\u00fcr Energietechnik (ZET), University of Bayreuth, Universit\u00e4tsstra\u00dfe 30, 95440 Bayreuth, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6960-9805","authenticated-orcid":false,"given":"Ralf","family":"Moos","sequence":"additional","affiliation":[{"name":"Department of Functional Materials, Bayreuth Engine Research Center (BERC) and Zentrum f\u00fcr Energietechnik (ZET), University of Bayreuth, Universit\u00e4tsstra\u00dfe 30, 95440 Bayreuth, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ulrich","family":"Simon","sequence":"additional","affiliation":[{"name":"Institute of Inorganic Chemistry (IAC) and Center for Automotive Catalytic Systems Aachen (ACA), RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,11,13]]},"reference":[{"key":"ref_1","unstructured":"Database of Zeolite Structures. 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