{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T05:43:03Z","timestamp":1781847783692,"version":"3.54.5"},"reference-count":49,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,11]],"date-time":"2023-05-11T00:00:00Z","timestamp":1683763200000},"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>Simple, low-cost methods for sensing volatile organic compounds that leave no trace and do not have a detrimental effect on the environment are able to protect communities from the impacts of contaminants in water supplies. This paper reports the development of a portable, autonomous, Internet of Things (IoT) electrochemical sensor for detecting formaldehyde in tap water. The sensor is assembled from electronics, i.e., a custom-designed sensor platform and developed HCHO detection system based on Ni(OH)2\u2013Ni nanowires (NWs) and synthetic-paper-based, screen-printed electrodes (pSPEs). The sensor platform, consisting of the IoT technology, a Wi-Fi communication system, and a miniaturized potentiostat can be easily connected to the Ni(OH)2\u2013Ni NWs and pSPEs via a three-terminal electrode. The custom-made sensor, which has a detection capability of 0.8 \u00b5M\/24 ppb, was tested for an amperometric determination of the HCHO in deionized (DI) and tap-water-based alkaline electrolytes. This promising concept of an electrochemical IoT sensor that is easy to operate, rapid, and affordable (it is considerably cheaper than any lab-grade potentiostat) could lead to the straightforward detection of HCHO in tap water.<\/jats:p>","DOI":"10.3390\/s23104676","type":"journal-article","created":{"date-parts":[[2023,5,12]],"date-time":"2023-05-12T01:30:29Z","timestamp":1683855029000},"page":"4676","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["IoT Electrochemical Sensor with Integrated Ni(OH)2\u2013Ni Nanowires for Detecting Formaldehyde in Tap Water"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3598-296X","authenticated-orcid":false,"given":"\u0160pela","family":"Trafela","sequence":"first","affiliation":[{"name":"Department for Nanostructured Materials, Jo\u017eef Stefan Institute, Jamova c. 39, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abhilash","family":"Krishnamurthy","sequence":"additional","affiliation":[{"name":"Department for Nanostructured Materials, Jo\u017eef Stefan Institute, Jamova c. 39, 1000 Ljubljana, Slovenia"},{"name":"Jo\u017eef Stefan International Postgraduate School, Jamova c. 39, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9987-7221","authenticated-orcid":false,"given":"Kristina \u017dagar","family":"Soder\u017enik","sequence":"additional","affiliation":[{"name":"Department for Nanostructured Materials, Jo\u017eef Stefan Institute, Jamova c. 39, 1000 Ljubljana, Slovenia"},{"name":"Jo\u017eef Stefan International Postgraduate School, Jamova c. 39, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1840-4209","authenticated-orcid":false,"given":"Ur\u0161ka","family":"Kav\u010di\u010d","sequence":"additional","affiliation":[{"name":"Pulp and Paper Institute, Bogi\u0161i\u0107eva 8, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Igor","family":"Karlovits","sequence":"additional","affiliation":[{"name":"Pulp and Paper Institute, Bogi\u0161i\u0107eva 8, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beno","family":"Klop\u010di\u010d","sequence":"additional","affiliation":[{"name":"Department for Nanostructured Materials, Jo\u017eef Stefan Institute, Jamova c. 39, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0019-7491","authenticated-orcid":false,"given":"Sa\u0161o","family":"\u0160turm","sequence":"additional","affiliation":[{"name":"Department for Nanostructured Materials, Jo\u017eef Stefan Institute, Jamova c. 39, 1000 Ljubljana, Slovenia"},{"name":"Jo\u017eef Stefan International Postgraduate School, Jamova c. 39, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristina","family":"\u017du\u017eek","sequence":"additional","affiliation":[{"name":"Department for Nanostructured Materials, Jo\u017eef Stefan Institute, Jamova c. 39, 1000 Ljubljana, Slovenia"},{"name":"Jo\u017eef Stefan International Postgraduate School, Jamova c. 39, 1000 Ljubljana, Slovenia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1016\/j.snb.2010.03.090","article-title":"Effective analysis of gaseous formaldehyde based on a platinum-deposited screen-printed edge band ultramicroelectrode coated with Nafion as solid polymer electrolyte","volume":"147","author":"Chou","year":"2010","journal-title":"Sens. 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