{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:43:32Z","timestamp":1769561012609,"version":"3.49.0"},"reference-count":89,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,9]],"date-time":"2025-01-09T00:00:00Z","timestamp":1736380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["22-19-00703"],"award-info":[{"award-number":["22-19-00703"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Nanocrystalline TiO2 is a perspective semiconductor gas-sensing material due to its long-term stability of performance, but it is limited in application because of high electrical resistance. In this paper, a gas-sensing nanocomposite material with p-p heterojunction is introduced based on p-conducting Cr-doped TiO2 in combination with p-conducting Cr2O3. Materials were synthesized via a single-step flame spray pyrolysis (FSP) technique and comprehensively studied by X-ray diffraction (XRD), Brunauer\u2013Emmett\u2013Teller (BET) specific surface area analysis, transition electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy, X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and Raman spectroscopy. Gas sensor performance in direct current (DC) mode was studied toward a number of gasses (H2, CO, CH4, NO2, H2S, NH3) as well as volatile organic compounds (VOCs) (acetone, methanol, and formaldehyde) in dry and humid conditions. The long-term stability of the obtained materials\u2019 gas sensor performance was evaluated alongside with an ex situ study of structural evolution. High sensitivity toward oxygenated VOCs and a lower detection limit below ppm level with a limited influence of humidity were shown. The long-term gas sensor performance stability of the obtained materials and its connection to the defect structure of doped TiO2 is demonstrated.<\/jats:p>","DOI":"10.3390\/ijms26020499","type":"journal-article","created":{"date-parts":[[2025,1,9]],"date-time":"2025-01-09T07:00:47Z","timestamp":1736406047000},"page":"499","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Cr-Doped Nanocrystalline TiO2-Cr2O3 Nanocomposites with p-p Heterojunction as a Stable Gas-Sensitive Material"],"prefix":"10.3390","volume":"26","author":[{"given":"Dmitriy","family":"Kuranov","sequence":"first","affiliation":[{"name":"Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4542-6999","authenticated-orcid":false,"given":"Elizaveta","family":"Konstantinova","sequence":"additional","affiliation":[{"name":"Physics Department, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anastasia","family":"Grebenkina","sequence":"additional","affiliation":[{"name":"Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alina","family":"Sagitova","sequence":"additional","affiliation":[{"name":"Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2151-9592","authenticated-orcid":false,"given":"Vadim","family":"Platonov","sequence":"additional","affiliation":[{"name":"Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sergei","family":"Polomoshnov","sequence":"additional","affiliation":[{"name":"National Research University of Electronic Technology, Institute of Integrated Electronics and Microsystems, 124498 Moscow, Russia"},{"name":"Scientific-Manufacturing Complex Technological Centre, 124498 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3354-0885","authenticated-orcid":false,"given":"Marina","family":"Rumyantseva","sequence":"additional","affiliation":[{"name":"Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2247-9388","authenticated-orcid":false,"given":"Valeriy","family":"Krivetskiy","sequence":"additional","affiliation":[{"name":"Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia"},{"name":"Scientific-Manufacturing Complex Technological Centre, 124498 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kanan, S., Obeideen, K., Moyet, M., Abed, H., Khan, D., Shabnam, A., El-Sayed, Y., Arooj, M., and Mohamed, A.A. 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