{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:35:42Z","timestamp":1792805742212,"version":"4.5.0"},"reference-count":69,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,18]],"date-time":"2025-06-18T00:00:00Z","timestamp":1750204800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Directorate of the Pedagogical and Technological University of Colombia SGI 3804","award":["FINU 010-2022"],"award-info":[{"award-number":["FINU 010-2022"]}],"id":[{"id":"https:\/\/ror.org\/04vdmbk59","id-type":"ROR","asserted-by":"crossref"}]},{"name":"Francisco de Paula Santander University","award":["FINU 010-2022"],"award-info":[{"award-number":["FINU 010-2022"]}],"id":[{"id":"https:\/\/ror.org\/01vwm8t51","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>In this work, we report the evaluation of a (CuO\/WO3)-CuWO4 heterostructured system as a methanol and acetone gas sensor in different configurations, contrasted with the pure oxides CuO and WO3. The samples were synthesized using a modified precipitation route followed by a single thermal treatment step to induce multiphase simultaneous crystallization. The structural characterization by XRD showed that all the materials presented the formation of monoclinic CuO and WO3 and triclinic CuWO4. No additional phases were detected in the samples, and a reduction in the crystallite size of the CuO phase after the crystallization in the heterostructured system was observed. FE-SEM analysis made it possible to directly observe the morphology and the structures of the samples at the nanometer scale, showing a heterogeneous grain formation and supporting the formation of a heterostructure. UV-Vis DRS was used to study the optical properties of the materials, and the presence of two optical band gaps was successfully determined, which provides further evidence of heterostructure formation via this modified synthesis route. The variation in the resistance of the materials was observed in the presence of methanol and acetone vapors, where the heterostructure exhibited a substantial change in performance in the configuration with 40% copper precursor (Cu40:W60), the sample that presented the highest response as a sensor against these VOCs. To our knowledge, this is the first time that this system has been reported as a gas sensor, using the multiple configurations of the (CuO\/WO3)-CuWO4 heterostructured system.<\/jats:p>","DOI":"10.3390\/ma18122896","type":"journal-article","created":{"date-parts":[[2025,6,19]],"date-time":"2025-06-19T05:08:39Z","timestamp":1750309719000},"page":"2896","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Gas Sensor Properties of (CuO\/WO3)-CuWO4 Heterostructured Nanocomposite Materials"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1705-8677","authenticated-orcid":false,"given":"Michael","family":"Castaneda Mendoza","sequence":"first","affiliation":[{"name":"Grupo F\u00edsica de Materiales\u2014GFM, Universidad Pedag\u00f3gica y Tecnol\u00f3gica de Colombia, Avenida Central Del Norte 39-115, Tunja 150003, Boyac\u00e1, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos","family":"Parra Vargas","sequence":"additional","affiliation":[{"name":"Grupo F\u00edsica de Materiales\u2014GFM, Universidad Pedag\u00f3gica y Tecnol\u00f3gica de Colombia, Avenida Central Del Norte 39-115, Tunja 150003, Boyac\u00e1, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4209-1698","authenticated-orcid":false,"given":"Miryam","family":"Rinc\u00f3n Joya","sequence":"additional","affiliation":[{"name":"Grupo de F\u00edsica Mesosc\u00f3pica, Universidad Nacional de Colombia, Carrera 30 Calle 45-03, Bogot\u00e1 111321, Cundinamarca, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2498-4820","authenticated-orcid":false,"given":"Adenilson","family":"Chiquito","sequence":"additional","affiliation":[{"name":"NanoLab, Departamento de F\u00edsica, Universidade Federal de S\u00e3o Carlos, Rodovia Washington Luiz km 235, S\u00e3o Carlos 13565-905, S\u00e3o Paulo, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela","family":"Raba-P\u00e1ez","sequence":"additional","affiliation":[{"name":"Grupo de Investigaci\u00f3n en Materiales Polim\u00e9ricos\u2014GIMAPOL, Universidad Francisco de Paula Santander, Avenida Gran Colombia 12E-96, C\u00facuta 540003, Norte de Santander, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"167464","DOI":"10.1016\/j.scitotenv.2023.167464","article-title":"Emission characteristics, environmental impact, and health risk assessment of volatile organic compounds (VOCs) during manicure processes","volume":"906","author":"Hao","year":"2024","journal-title":"Sci. Total Environ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1039\/C6EN00478D","article-title":"WO3-based photocatalysts: Morphology control, activity enhancement and multifunctional applications","volume":"4","author":"Dong","year":"2017","journal-title":"Environ. Sci. Nano"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"817","DOI":"10.1039\/C9QI01516G","article-title":"Tungsten oxide-based visible light-driven photocatalysts: Crystal and electronic structures and strategies for photocatalytic efficiency enhancement","volume":"7","author":"Quan","year":"2020","journal-title":"Inorg. Chem. Front."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1591","DOI":"10.1016\/j.apt.2018.03.024","article-title":"Understanding the morphological effects of WO3 photocatalysts for the degradation of organic pollutants","volume":"29","author":"Adhikari","year":"2018","journal-title":"Adv. Powder Technol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1016\/j.carbon.2016.07.045","article-title":"Nanoporous carbon\/WO3 anodes for an enhanced water photooxidation","volume":"108","author":"Celorrio","year":"2016","journal-title":"Carbon"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2955","DOI":"10.1557\/jmr.2019.189","article-title":"WO3 nanocubes: Hydrothermal synthesis, growth mechanism, and photocatalytic performance","volume":"34","author":"Wang","year":"2019","journal-title":"J. Mater. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"7780","DOI":"10.1021\/ja800835q","article-title":"Pristine simple oxides as visible light driven photocatalysts: Highly efficient decomposition of organic compounds over platinum-loaded tungsten oxide","volume":"130","author":"Abe","year":"2008","journal-title":"J. Am. Chem. Soc."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1479","DOI":"10.1111\/ijac.13467","article-title":"Visible light active heterostructured photocatalyst system based on CuO plate-like particles and SnO 2 nanofibers","volume":"17","author":"Dursun","year":"2020","journal-title":"Int. J. Appl. Ceram. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"104919","DOI":"10.1016\/j.mssp.2020.104919","article-title":"Hydrothermal\/electrospinning synthesis of CuO plate-like particles\/TiO2 fibers heterostructures for high-efficiency photocatalytic degradation of organic dyes and phenolic pollutants","volume":"109","author":"Dursun","year":"2020","journal-title":"Mater. Sci. Semicond. Process."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2603","DOI":"10.1039\/C5CS00838G","article-title":"Hierarchical photocatalysts","volume":"45","author":"Li","year":"2016","journal-title":"Chem. Soc. Rev."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1374","DOI":"10.1016\/j.msec.2019.02.048","article-title":"CuO\/WO3 nanoparticles decorated graphene oxide nanosheets with enhanced peroxidase-like activity for electrochemical cancer cell detection and targeted therapeutics","volume":"99","author":"Alizadeh","year":"2019","journal-title":"Mater. Sci. Eng. C"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.jallcom.2019.04.157","article-title":"Electrospun n-p WO3\/CuO heterostructure nanofibers as an efficient sarin nerve agent sensing material at room temperature","volume":"793","author":"Alali","year":"2019","journal-title":"J. Alloys Compd."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"200","DOI":"10.1016\/j.pnsc.2018.03.004","article-title":"WO3 nanoflakes decorated with CuO clusters for enhanced photoelectrochemical water splitting","volume":"28","author":"Wang","year":"2018","journal-title":"Prog. Nat. Sci. Mater. Int."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"101390","DOI":"10.1016\/j.jwpe.2020.101390","article-title":"Production of CuO\u2013WO3 hybrids and their dye removal capacity\/performance from wastewater by adsorption\/photocatalysis","volume":"36","author":"Dursun","year":"2020","journal-title":"J. Water Process Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"141616","DOI":"10.1016\/j.cej.2023.141616","article-title":"Visible photocatalytic hydrogen production from CH3OH over CuO\/WO3: The effect of electron transfer behavior of the adsorbed CH3OH","volume":"459","author":"Wang","year":"2023","journal-title":"Chem. Eng. J."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1016\/j.jallcom.2019.01.349","article-title":"Highly sensitive and selective H2S gas sensors based on flower-like WO3\/CuO composites operating at low\/room temperature","volume":"788","author":"He","year":"2019","journal-title":"J. Alloys Compd."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.aca.2018.09.020","article-title":"\u201cMetal oxide\u2014Based heterostructures for gas sensors\u201d\u2014A review","volume":"1039","author":"Zappa","year":"2018","journal-title":"Anal. Chim. Acta"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Danish, M.S.S., Estrella-Pajulas, L., Alemaida, I., Lisin, A., Moiseev, N., Ahmadi, M., Nazari, M., Wali, M., Zaheb, H., and Senjyu, T. (2021). Photocatalytic Applications of Metal Oxides for Sustainable Environmental Remediation. Met.\u2014Open Access Metall. J., 11.","DOI":"10.3390\/met11010080"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1002\/ppsc.201500178","article-title":"CuO\/WO3 Hybrid Nanocubes for High-Responsivity and Fast-Recovery H2S Sensors Operated at Low Temperature","volume":"33","author":"Yu","year":"2016","journal-title":"Part. Part. Syst. Charact."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"967","DOI":"10.1016\/j.ijhydene.2024.03.004","article-title":"In situ fabrication of WO3\/CuWO4\/CuO heterojunction photoanode for boosted interfacial charge transfer and enhanced photoelectrochemical water splitting","volume":"61","author":"Li","year":"2024","journal-title":"Int. J. Hydrog. Energy"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Raba-P\u00e1ez, A.M., Malafatti, J.O.D., Parra-Vargas, C.A., Paris, E.C., and Rinc\u00f3n-Joya, M. (2020). Effect of tungsten doping on the structural, morphological and bactericidal properties of nanostructured CuO. PLoS ONE, 15.","DOI":"10.1371\/journal.pone.0239868"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Huang, J., and Wan, Q. (2009). Gas Sensors Based on Semiconducting Metal Oxide One-Dimensional Nanostructures. Sensors, 9.","DOI":"10.3390\/s91209903"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1007\/s10909-023-02963-5","article-title":"Structural and Magnetic Properties of Nd3Ba5Cu8O18+\u1e9f Superconductor","volume":"211","author":"Gaona","year":"2023","journal-title":"J. Low Temp. Phys."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"171827","DOI":"10.1016\/j.jmmm.2024.171827","article-title":"Magnetic and electrical behaviour of Yb substitution on Bi1-xYbxFeO3 (0.00 < x < 0.06) ceramic system","volume":"593","author":"Supelano","year":"2024","journal-title":"J. Magn. Magn. Mater."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Pallavolu, M.-R., Banerjee, A.-N., and Joo, S.-W. (2023). Battery-Type Behavior of Al-Doped CuO Nanoflakes to Fabricate a High-Performance Hybrid Supercapacitor Device for Superior Energy Storage Applications. Coatings, 13.","DOI":"10.3390\/coatings13081337"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"141212","DOI":"10.1016\/j.chemosphere.2024.141212","article-title":"Green synthesis of CuO\/Fe2O3\/ZnO ternary composite photocatalyst using grape extract for enhanced photodegradation of environmental organic pollutant","volume":"351","author":"Jansanthea","year":"2024","journal-title":"Chemosphere"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"11568","DOI":"10.1007\/s10853-023-08687-x","article-title":"Efficient room temperature carbon dioxide gas sensor based on barium doped CuO thin films","volume":"58","author":"Abdelkarem","year":"2023","journal-title":"J. Mater. Sci."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"110614","DOI":"10.1016\/j.materresbull.2019.110614","article-title":"Structural design of hexagonal\/monoclinic WO3 phase junction for photocatalytic degradation","volume":"121","author":"Kang","year":"2020","journal-title":"Mater. Res. Bull."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"135340","DOI":"10.1016\/j.matlet.2023.135340","article-title":"Structure, optical, colorimetric, and supercapacitor properties of anode \u03b1-CuWO4 crystals","volume":"354","author":"Reis","year":"2024","journal-title":"Mater. Lett."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"e202401045","DOI":"10.1002\/cctc.202401045","article-title":"Improved Catalytic Partial Oxidation of Methane via Lattice Oxygen Modification on Supported Copper Oxide Catalyst System","volume":"16","author":"Ohyama","year":"2024","journal-title":"ChemCatChem"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2110","DOI":"10.1021\/acs.analchem.2c05143","article-title":"Room-Temperature Optoelectronic Gas Sensor Based on Core\u2013Shell g-C3N4@WO3 Heterocomposites for Efficient Ammonia Detection","volume":"95","author":"Zou","year":"2023","journal-title":"Anal. Chem."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"108563","DOI":"10.1016\/j.sse.2022.108563","article-title":"Effects of oxygen gas in the sputtering process of the WO3 sensing layer on NO2 sensing characteristics of the FET-type gas sensor","volume":"200","author":"Jeong","year":"2023","journal-title":"Solid-State Electron."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"320","DOI":"10.1016\/j.matchemphys.2018.12.061","article-title":"X-ray diffraction Rietveld analysis and Bond Valence analysis of nano titania containing oxygen vacancies synthesized via sol-gel route","volume":"225","author":"Murugesan","year":"2019","journal-title":"Mater. Chem. Phys."},{"key":"ref_34","unstructured":"Cuervo Farf\u00e1n, J.A. (2021). Producci\u00f3n y Propiedades F\u00edsicas de Nuevas Perovskitas Complejas del Tipo RAMOX (R = La, Nd, Sm, Eu; A = Sr, Bi; M = Ti, Mn, Fe). [Ph.D. Thesis, Universidad Nacional de Colombia]. Available online: https:\/\/repositorio.unal.edu.co\/handle\/unal\/79915."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"e27740","DOI":"10.1016\/j.heliyon.2024.e27740","article-title":"Innovations in WO3 gas sensors: Nanostructure engineering, functionalization, and future perspectives","volume":"10","author":"Li","year":"2024","journal-title":"Heliyon"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"160070","DOI":"10.1016\/j.jallcom.2021.160070","article-title":"Dy-doped MoO3 nanobelts synthesized via hydrothermal route: Influence of Dy contents on the structural, morphological and optical properties","volume":"876","author":"Sen","year":"2021","journal-title":"J. Alloys Compd."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"012021","DOI":"10.1088\/1742-6596\/979\/1\/012021","article-title":"Dislocation, crystallite size distribution and lattice strain of magnesium oxide nanoparticles","volume":"979","author":"Sutapa","year":"2018","journal-title":"J. Phys. Conf. Ser."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1395","DOI":"10.1016\/j.jmrt.2024.07.181","article-title":"Enhancement mechanisms of mechanical, electrical and thermal properties of carbon nanotube-copper composites: A review","volume":"32","author":"Jia","year":"2024","journal-title":"J. Mater. Res. Technol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"100733","DOI":"10.1016\/j.jsamd.2024.100733","article-title":"Study on structural, morphological, elastic and electrical properties of ZnO nanoparticles for electronic device applications","volume":"9","author":"Hegde","year":"2024","journal-title":"J. Sci. Adv. Mater. Devices"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"545","DOI":"10.1016\/j.apsusc.2013.01.084","article-title":"Effect of magnetism on the ethanol sensitivity of undoped and Mn-doped CuO nanoflakes","volume":"270","author":"Mariammal","year":"2013","journal-title":"Appl. Surf. Sci."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"110859","DOI":"10.1016\/j.diamond.2024.110859","article-title":"A eco-friendly, green synthesis of Ag loaded WO3\/rGO nanocomposites for effective UV light photocatalytic degradation of 4-nitrophenol and antimicrobial activity","volume":"142","author":"Vanasundari","year":"2024","journal-title":"Diam. Relat. Mater."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"7642","DOI":"10.1016\/j.ceramint.2020.11.106","article-title":"Synthesis and Characterization of Hetero-metallic Oxides-Reduced Graphene Oxide Nanocomposites for Photocatalytic Applications","volume":"47","author":"Fatima","year":"2021","journal-title":"Ceram. Int."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"228","DOI":"10.1007\/s10971-020-05433-6","article-title":"Effect of hydrothermal temperature on the antibacterial and photocatalytic activity of WO3 decorated with silver nanoparticles","volume":"97","author":"Capeli","year":"2021","journal-title":"J. Sol-Gel Sci. Technol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1007\/s10904-013-9970-2","article-title":"Facile Chemical Synthesis and Characterization of Copper Tungstate Nanoparticles","volume":"24","author":"Pourmortazavi","year":"2014","journal-title":"J. Inorg. Organomet. Polym."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"110933","DOI":"10.1016\/j.inoche.2023.110933","article-title":"CuWO4 as a cost-effective electrocatalyst for urea oxidation reaction","volume":"154","author":"Sreekanth","year":"2023","journal-title":"Inorg. Chem. Commun."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"7610","DOI":"10.1021\/cr400544s","article-title":"Mechanisms of Nucleation and Growth of Nanoparticles in Solution","volume":"114","author":"Thanh","year":"2014","journal-title":"Chem. Rev."},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Xue, S., Cao, S., Huang, Z., Yang, D., and Zhang, G. (2021). Improving Gas-Sensing Performance Based on MOS Nanomaterials: A Review. Materials, 14.","DOI":"10.3390\/ma14154263"},{"key":"ref_48","first-page":"4744","article-title":"Effect of Ag doping on structural, optical and photocatalytic activity of tungsten oxide (WO3) nanoparticles","volume":"27","author":"Janaki","year":"2016","journal-title":"J. Mater. Sci: Mater. Electron."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"118588","DOI":"10.1016\/j.apcatb.2020.118588","article-title":"The role of electron transfer behavior induced by CO chemisorption on visible-light-driven CO conversion over WO3 and CuWO4\/WO3","volume":"265","author":"Wang","year":"2020","journal-title":"Appl. Catal. B Environ."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"114573","DOI":"10.1016\/j.ssc.2021.114573","article-title":"Use and misuse of the Kubelka-Munk function to obtain the band gap energy from diffuse reflectance measurements","volume":"341","author":"Landi","year":"2022","journal-title":"Solid State Commun."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"39058","DOI":"10.1016\/j.ijhydene.2021.09.136","article-title":"Fabrication of WO3 based nanocomposites for the excellent photocatalytic energy production under visible light irradiation","volume":"46","author":"Asiri","year":"2021","journal-title":"Int. J. Hydrog. Energy"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"e01505","DOI":"10.1016\/j.heliyon.2019.e01505","article-title":"Automated method for the determination of the band gap energy of pure and mixed powder samples using diffuse reflectance spectroscopy","volume":"5","year":"2019","journal-title":"Heliyon"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1426","DOI":"10.1007\/s12596-022-00961-6","article-title":"Influence of the secondary absorption and the vertical axis scale of the Tauc\u2019s plot on optical bandgap energy","volume":"52","author":"Jubu","year":"2023","journal-title":"J. Opt."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"5054","DOI":"10.1007\/s12596-024-01741-0","article-title":"Considerations about the determination of optical bandgap from diffuse reflectance spectroscopy using the tauc plot","volume":"53","author":"Jubu","year":"2024","journal-title":"J. Opt."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"9638","DOI":"10.1039\/C4TA07213H","article-title":"Incorporation of Ag nanowires in CuWO4 for improved visible light-induced photoanode performance","volume":"3","author":"Zhang","year":"2015","journal-title":"J. Mater. Chem. A"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"101886","DOI":"10.1016\/j.mtcomm.2020.101886","article-title":"Structural evolution, optical properties, and photocatalytic performance of copper and tungsten heterostructure materials","volume":"26","author":"Malafatti","year":"2021","journal-title":"Mater. Today Commun."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"106019","DOI":"10.1016\/j.rinp.2022.106019","article-title":"Enlargement of band gaps on thermal wave crystals by using heterostructures","volume":"42","year":"2022","journal-title":"Results Phys."},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Yao, Y., Sang, D., Zou, L., Wang, Q., and Liu, C. (2021). A Review on the Properties and Applications of WO3 Nanostructure-Based Optical and Electronic Devices. Nanomaterials, 11.","DOI":"10.3390\/nano11082136"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/j.physe.2019.01.006","article-title":"Morphology controllable synthesis of hierarchical WO3 nanostructures and C2H2 sensing properties","volume":"109","author":"Wei","year":"2019","journal-title":"Phys. E Low-Dimens. Syst. Nanostructures"},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"052106","DOI":"10.1063\/1.4975208","article-title":"Fabrication and high temperature electronic behaviors of n-WO3 nanorods\/p-diamond heterojunction","volume":"110","author":"Wang","year":"2017","journal-title":"Appl. Phys. Lett."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"126","DOI":"10.1016\/j.solidstatesciences.2018.03.002","article-title":"Nonlinear current-voltage characteristics of WO3-x nano-\/micro-rods","volume":"78","author":"Shen","year":"2018","journal-title":"Solid State Sci."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"113578","DOI":"10.1016\/j.sna.2022.113578","article-title":"Nanostructured metal oxide semiconductor-based gas sensors: A comprehensive review","volume":"341","author":"Krishna","year":"2022","journal-title":"Sens. Actuators A Phys."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"6850","DOI":"10.1021\/acs.analchem.9b01089","article-title":"Ten Nanometer Scale WO3\/CuO Heterojunction Nanochannel for an Ultrasensitive Chemical Sensor","volume":"91","author":"Cho","year":"2019","journal-title":"Anal. Chem."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"e12604","DOI":"10.1002\/eng2.12604","article-title":"Metal oxide semiconductors for gas sensing","volume":"5","author":"Goel","year":"2023","journal-title":"Eng. Rep."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/j.snb.2019.05.049","article-title":"Conduction mechanisms in one dimensional core-shell nanostructures for gas sensing: A review","volume":"295","author":"Karnati","year":"2019","journal-title":"Sens. Actuators B Chem."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"965","DOI":"10.1039\/b716745h","article-title":"Chemical synthesis, characterisation and gas sensing performance of copper oxide nanoribbons","volume":"18","author":"Gou","year":"2008","journal-title":"J. Mater. Chem."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"649","DOI":"10.1016\/j.ceramint.2008.01.028","article-title":"Ethanol sensing properties of CuO nanowires prepared by an oxidation reaction","volume":"35","author":"Raksa","year":"2009","journal-title":"Ceram. Int."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"358","DOI":"10.1016\/j.proeng.2012.09.157","article-title":"Synthesis of WO3 Nanorod based Thin Films for Ethanol and H2 Sensing","volume":"47","author":"Ahmad","year":"2012","journal-title":"Procedia Eng."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1016\/j.jcis.2018.04.013","article-title":"Characteristics of binary WO3@CuO and ternary WO3@PDA@CuO based on impressive sensing acetone odor","volume":"524","author":"Yang","year":"2018","journal-title":"J. Colloid Interface Sci."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/12\/2896\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:54:35Z","timestamp":1760032475000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/12\/2896"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,6,18]]},"references-count":69,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2025,6]]}},"alternative-id":["ma18122896"],"URL":"https:\/\/doi.org\/10.3390\/ma18122896","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,6,18]]}}}