{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T12:09:39Z","timestamp":1780488579761,"version":"3.54.1"},"reference-count":45,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,15]],"date-time":"2023-06-15T00:00:00Z","timestamp":1686787200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Russian Science Foundation","award":["22-29-00621"],"award-info":[{"award-number":["22-29-00621"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Thin nanocomposite films based on zinc oxide (ZnO) added with cobalt oxide (Co3O4) were synthesized by solid-phase pyrolysis. According to XRD, the films consist of a ZnO wurtzite phase and a cubic structure of Co3O4 spinel. The crystallite sizes in the films increased from 18 nm to 24 nm with growing annealing temperature and Co3O4 concentration. Optical and X-ray photoelectron spectroscopy data revealed that enhancing the Co3O4 concentration leads to a change in the optical absorption spectrum and the appearance of allowed transitions in the material. Electrophysical measurements showed that Co3O4-ZnO films have a resistivity up to 3 \u00d7 104 Ohm\u2219cm and a semiconductor conductivity close to intrinsic. With advancing the Co3O4 concentration, the mobility of the charge carriers was found to increase by almost four times. The photosensors based on the 10Co-90Zn film exhibited a maximum normalized photoresponse when exposed to radiation with wavelengths of 400 nm and 660 nm. It was found that the same film has a minimum response time of ca. 26.2 ms upon exposure to radiation of 660 nm wavelength. The photosensors based on the 3Co-97Zn film have a minimum response time of ca. 58.3 ms versus the radiation of 400 nm wavelength. Thus, the Co3O4 content was found to be an effective impurity to tune the photosensitivity of radiation sensors based on Co3O4-ZnO films in the wavelength range of 400\u2013660 nm.<\/jats:p>","DOI":"10.3390\/s23125617","type":"journal-article","created":{"date-parts":[[2023,6,16]],"date-time":"2023-06-16T02:54:33Z","timestamp":1686884073000},"page":"5617","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Nanocomposite Co3O4-ZnO Thin Films for Photoconductivity Sensors"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3725-6053","authenticated-orcid":false,"given":"Victor V.","family":"Petrov","sequence":"first","affiliation":[{"name":"Institute of Nanotechnologies, Electronics, and Equipment Engineering, Southern Federal University, Taganrog 347922, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0372-1802","authenticated-orcid":false,"given":"Victor V.","family":"Sysoev","sequence":"additional","affiliation":[{"name":"Institute of Physics and Technology, Yuri Gagarin State Technical University of Saratov, Saratov 410054, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irina O.","family":"Ignatieva","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry, Southern Federal University, Rostov-on-Don 344090, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irina A.","family":"Gulyaeva","sequence":"additional","affiliation":[{"name":"Institute of Nanotechnologies, Electronics, and Equipment Engineering, Southern Federal University, Taganrog 347922, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria G.","family":"Volkova","sequence":"additional","affiliation":[{"name":"Institute of Nanotechnologies, Electronics, and Equipment Engineering, Southern Federal University, Taganrog 347922, Russia"},{"name":"Faculty of Chemistry, Southern Federal University, Rostov-on-Don 344090, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra P.","family":"Ivanishcheva","sequence":"additional","affiliation":[{"name":"Institute of Nanotechnologies, Electronics, and Equipment Engineering, Southern Federal University, Taganrog 347922, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0348-8059","authenticated-orcid":false,"given":"Soslan A.","family":"Khubezhov","sequence":"additional","affiliation":[{"name":"Institute of Nanotechnologies, Electronics, and Equipment Engineering, Southern Federal University, Taganrog 347922, Russia"},{"name":"Core Shared Research Facility \u00abPhysics and Technology of Nanostructures\u00bb, North-Ossetian State University, Vladikavkaz 362025, Russia"},{"name":"Department of Physics and Engineering, ITMO University, St. Petersburg 197101, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuri N.","family":"Varzarev","sequence":"additional","affiliation":[{"name":"Institute of Nanotechnologies, Electronics, and Equipment Engineering, Southern Federal University, Taganrog 347922, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8445-9139","authenticated-orcid":false,"given":"Ekaterina M.","family":"Bayan","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry, Southern Federal University, Rostov-on-Don 344090, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1007\/s10854-022-09470-5","article-title":"Enhancing the electrical conductivity and the dielectric features of ZnO nanoparticles through Co doping effect for energy storage applications","volume":"34","author":"Saadi","year":"2023","journal-title":"J. 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