{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T22:15:26Z","timestamp":1776982526603,"version":"3.51.4"},"reference-count":20,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2015,4,7]],"date-time":"2015-04-07T00:00:00Z","timestamp":1428364800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We prepared 0.1 wt%\u201330 wt% Pd-loaded Co3O4 by a colloidal mixing method and investigated the sensing properties of a Pd-loaded Co3O4 sensor element, such as the sensor response, 90% response time, 90% recovery time, and signal-to-noise (S\/N) ratio, toward low nitric oxide (NO) gas levels in the range from 50 to 200 parts per billion. The structural properties of the Pd-loaded Co3O4 powder were investigated using X-ray diffraction analysis and transmission electron microscopy. Pd in the powder existed as PdO. The sensor elements with 0.1 wt%\u201310 wt% Pd content have higher sensor properties than those without any Pd content. The response of the sensor element with a 30 wt% Pd content decreased markedly because of the aggregation and poor dispersibility of the PdO particles. High sensor response and S\/N ratio toward the NO gas were achieved when a sensor element with 10 wt% Pd content was used.<\/jats:p>","DOI":"10.3390\/s150408109","type":"journal-article","created":{"date-parts":[[2015,4,8]],"date-time":"2015-04-08T03:01:07Z","timestamp":1428462067000},"page":"8109-8120","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Sensing Properties of Pd-Loaded Co3O4 Film for a ppb-Level NO Gas Sensor"],"prefix":"10.3390","volume":"15","author":[{"given":"Takafumi","family":"Akamatsu","sequence":"first","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Inorganic Functional Materials Research Institute, 2266-98, Anagahora, Shimo-Shidami, Moriyama-ku,  Nagoya-shi 463-8560, Japan"}]},{"given":"Toshio","family":"Itoh","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Inorganic Functional Materials Research Institute, 2266-98, Anagahora, Shimo-Shidami, Moriyama-ku,  Nagoya-shi 463-8560, Japan"}]},{"given":"Noriya","family":"Izu","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Inorganic Functional Materials Research Institute, 2266-98, Anagahora, Shimo-Shidami, Moriyama-ku,  Nagoya-shi 463-8560, Japan"}]},{"given":"Woosuck","family":"Shin","sequence":"additional","affiliation":[{"name":"National Institute of Advanced Industrial Science and Technology (AIST), Inorganic Functional Materials Research Institute, 2266-98, Anagahora, Shimo-Shidami, Moriyama-ku,  Nagoya-shi 463-8560, Japan"}]},{"given":"Kazuo","family":"Sato","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Aichi Institute of Technology, 1247, Yachigusa,  Yakusa-cho, Toyota-shi 470-0392, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2015,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1093\/jn\/128.1.79","article-title":"Breath hydrogen and methane expiration in men and women after oat extract consumption","volume":"128","author":"Behall","year":"1998","journal-title":"J. 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