{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:13:37Z","timestamp":1760235217581,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,7,30]],"date-time":"2021-07-30T00:00:00Z","timestamp":1627603200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Processes"],"abstract":"<jats:p>In this work,\u00a0Nb5+\u00a0and In3+\u00a0ions were used as dopants in titanium\/tungsten oxide nanostructures that are produced by the electrospinning and sintering process, for relative humidity (RH) detection. The microstructural properties were investigated by SEM, EDS, XRD, Raman and FTIR techniques. The electrical response characterization of the samples was performed by electrical impedance spectroscopy in the range of 400 Hz to 40 MHz, at 20 \u00b0C. The sensors sensitivity to moisture was evaluated in terms of the impedance variations to RH (10\u2013100%). The combined analysis of the microstructural characterization results confirmed the surface interaction between the oxides and the ions incorporation in Ti crystal lattice. All the studied sensors showed a conduction transition from p- to n-type at around 30\u201340% RH: besides, they also displayed better sensitivity to moisture than those obtained in a previous work using titanium\/tungsten combination using a different fabricationn route. The impedance modulus variation up to 1.1 and 1.3 orders of magnitude for the 4 wt % niobium and indium doped samples, respectively. The results are directly associated with the microstructure and alternative preparation process.<\/jats:p>","DOI":"10.3390\/pr9081336","type":"journal-article","created":{"date-parts":[[2021,8,1]],"date-time":"2021-08-01T21:44:32Z","timestamp":1627854272000},"page":"1336","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Effect of \u00a0Nb5+\u00a0and In3+\u00a0 Ions on Moisture Sensitivity of Electrospun Titanium\/Tungsten Oxide Nanostructures: Microstructural Characterization and Electrical Response"],"prefix":"10.3390","volume":"9","author":[{"given":"Georgenes M. G.","family":"Silva","sequence":"first","affiliation":[{"name":"Research Group on Electrospinning and Nanotechnology Applications, Department of Materials Science, Federal University of San Francisco Valley, Juazeiro 48902-300, Brazil"},{"name":"Federal Institute of Education, Science and Technology of the Sert\u00e3o Pernambucano, Petrolina 56314-520, Brazil"}]},{"given":"Victor N. S.","family":"Le\u00e3o","sequence":"additional","affiliation":[{"name":"Research Group on Electrospinning and Nanotechnology Applications, Department of Materials Science, Federal University of San Francisco Valley, Juazeiro 48902-300, Brazil"}]},{"given":"Michel F. G.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Research Group on Electrospinning and Nanotechnology Applications, Department of Materials Science, Federal University of San Francisco Valley, Juazeiro 48902-300, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5539-9766","authenticated-orcid":false,"given":"Pedro M.","family":"Faia","sequence":"additional","affiliation":[{"name":"CEMMPRE\u2013Electrical and Computer Engineering Department, University of Coimbra, FCTUC, Polo 2, Pinhal de Marrocos, 3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6302-2368","authenticated-orcid":false,"given":"Evando S.","family":"Ara\u00fajo","sequence":"additional","affiliation":[{"name":"Research Group on Electrospinning and Nanotechnology Applications, Department of Materials Science, Federal University of San Francisco Valley, Juazeiro 48902-300, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1007\/s42452-019-0592-3","article-title":"Metal oxide nanoparticles and their applications in nanotechnology","volume":"1","author":"Chavali","year":"2019","journal-title":"SN Appl. 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