{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T11:33:24Z","timestamp":1779190404647,"version":"3.51.4"},"reference-count":52,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,3,13]],"date-time":"2025-03-13T00:00:00Z","timestamp":1741824000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NSF-CREST Center for Innovation, Research, and Education in Environmental Nanotechnology (CIRE2N)","award":["HRD-1736093"],"award-info":[{"award-number":["HRD-1736093"]}]},{"name":"IUP USRC research grant award","award":["HRD-1736093"],"award-info":[{"award-number":["HRD-1736093"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study presents the fabrication and characterization of highly selective, room-temperature gas sensors based on ternary zinc oxide\u2013molybdenum disulfide\u2013titanium dioxide (ZnO-MoS2-TiO2) nanoheterostructures. Integrating two-dimensional (2D) MoS2 with oxide nano materials synergistically combines their unique properties, significantly enhancing gas sensing performance. Comprehensive structural and chemical analyses, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR), confirmed the successful synthesis and composition of the ternary nanoheterostructures. The sensors demonstrated excellent selectivity in detecting low concentrations of nitrogen dioxide (NO2) among target gases such as ammonia (NH3), methane (CH4), and carbon dioxide (CO2) at room temperature, achieving up to 58% sensitivity at 4 ppm and 6% at 0.1 ppm for NO2. The prototypes demonstrated outstanding selectivity and a short response time of approximately 0.51 min. The impact of light-assisted enhancement was examined under 1 mW\/cm2 weak ultraviolet (UV), blue, yellow, and red light-emitting diode (LED) illuminations, with the blue LED proving to deliver the highest sensor responsiveness. These results position ternary ZnO-MoS2-TiO2 nanoheterostructures as highly sensitive and selective room-temperature NO2 gas sensors that are suitable for applications in environmental monitoring, public health, and industrial processes.<\/jats:p>","DOI":"10.3390\/s25061781","type":"journal-article","created":{"date-parts":[[2025,3,13]],"date-time":"2025-03-13T06:53:00Z","timestamp":1741848780000},"page":"1781","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Highly Selective Room-Temperature Blue LED-Enhanced NO2 Gas Sensors Based on ZnO-MoS2-TiO2 Heterostructures"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-0758-1876","authenticated-orcid":false,"given":"Soraya Y.","family":"Flores","sequence":"first","affiliation":[{"name":"Department of Physics, University of Puerto Rico, San Juan, PR 00936, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elluz","family":"Pacheco","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Puerto Rico, San Juan, PR 00936, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8537-1390","authenticated-orcid":false,"given":"Carlos","family":"Malca","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Puerto Rico, San Juan, PR 00936, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoyan","family":"Peng","sequence":"additional","affiliation":[{"name":"Chongqing Key Laboratory of Brain-Inspired Computing and Intelligent Control, College of Artificial Intelligence, Southwest University, Chongqing 400715, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yihua","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Education, Shanghai Dianji University, Shanghai 201308, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Badi","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Biochemistry, and Physics, Indiana University of Pennsylvania, Indiana, PA 15705, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6331-761X","authenticated-orcid":false,"given":"Dalice M.","family":"Pinero","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Puerto Rico, San Juan, PR 00936, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6285-0102","authenticated-orcid":false,"given":"Liz M.","family":"Diaz-Vazquez","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Puerto Rico, San Juan, PR 00936, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4305-0409","authenticated-orcid":false,"given":"Andrew F.","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Biochemistry, and Physics, Indiana University of Pennsylvania, Indiana, PA 15705, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter X.","family":"Feng","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Puerto Rico, San Juan, PR 00936, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1007\/s40820-024-01543-w","article-title":"Smart Gas Sensors: Recent Developments and Future Prospective","volume":"17","author":"Zong","year":"2025","journal-title":"Nano-Micro Lett."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Li, G., Hou, J., Hilal, M., Kim, H., Chen, Z., Cui, Y., Kim, J.-H., and Cai, Z. 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