{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T12:59:23Z","timestamp":1780491563483,"version":"3.54.1"},"reference-count":29,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2016,8,15]],"date-time":"2016-08-15T00:00:00Z","timestamp":1471219200000},"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>Pure and copper (Cu)-incorporated tin oxide (SnO2) pellet gas sensors with characteristics provoking gas sensitivity were fabricated and used for measuring carbon monoxide (CO) atmospheres. Non-spherical pure SnO2 nano-structures were prepared by using urea as the precipitation agent. The resultant SnO2 powders were ball milled and incorporated with a transition metal, Cu, via chemical synthesis method. The incorporation is confirmed by high-resolution transmission electron microscope (HRTEM) analysis. By utilizing Cu-incorporated SnO2 pellets an increase in the CO sensitivity by an order of three, and a decrease in the response and recovery times by an order of two, were obtained. This improvement in the sensitivity is due to two factors that arise due to Cu incorporation: necks between the microparticles and stacking faults in the grains. These two factors increased the conductivity and oxygen adsorption, respectively, at the pellets\u2019 surface of SnO2 which, in turn, raised the CO sensitivity.<\/jats:p>","DOI":"10.3390\/s16081283","type":"journal-article","created":{"date-parts":[[2016,8,15]],"date-time":"2016-08-15T09:47:20Z","timestamp":1471254440000},"page":"1283","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["CO Gas Sensing Properties of Pure and Cu-Incorporated SnO2 Nanoparticles: A Study of Cu-Induced Modifications"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6071-3892","authenticated-orcid":false,"given":"Tangirala","family":"Karthik","sequence":"first","affiliation":[{"name":"Departamento de Ingenier\u00eda El\u00e9ctrica-SEES, Centro de Investigaci\u00f3n y de Estudios Avanzados del Instituto Polit\u00e9cnico Nacional, CINVESTAV-IPN, 14740 Apartado, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda","family":"Olvera","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda El\u00e9ctrica-SEES, Centro de Investigaci\u00f3n y de Estudios Avanzados del Instituto Polit\u00e9cnico Nacional, CINVESTAV-IPN, 14740 Apartado, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arturo","family":"Maldonado","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda El\u00e9ctrica-SEES, Centro de Investigaci\u00f3n y de Estudios Avanzados del Instituto Polit\u00e9cnico Nacional, CINVESTAV-IPN, 14740 Apartado, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heberto","family":"G\u00f3mez Pozos","sequence":"additional","affiliation":[{"name":"\u00c1rea acad\u00e9mica de Computaci\u00f3n y Electr\u00f3nica, ICBI, Universidad Aut\u00f3noma del Estado de Hidalgo, Mineral de la Reforma, 56092 Hidalgo, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,8,15]]},"reference":[{"key":"ref_1","unstructured":"Luiz, O. 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