{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T01:31:17Z","timestamp":1791250277000,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T00:00:00Z","timestamp":1774915200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007029","name":"Higher Education and Science Committee of MESCS RA","doi-asserted-by":"publisher","award":["21AG-2B011"],"award-info":[{"award-number":["21AG-2B011"]}],"id":[{"id":"10.13039\/501100007029","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>We report highly sensitive NO2 gas sensors based on ZnO thin films prepared via a sol\u2013gel method and deposited onto nanostructured black silicon (b-Si). The b-Si layers, fabricated using maskless reactive ion etching, consist of densely packed silicon nanoneedles with an average height of ~810 nm, a base diameter of ~160 nm, and a characteristic periodicity of ~190 nm. Owing to this highly developed surface morphology, the effective surface area of the b-Si layer is estimated to be approximately one order of magnitude higher than that of planar silicon, thereby enhancing gas adsorption and charge-transfer processes in the ZnO film. ZnO\/b-Si\/Si sensors exhibit a response of 448% at 25 ppm NO2 at an optimal operating temperature of 200 \u00b0C, which is approximately 1.5 times higher than that of planar ZnO\/Si sensors at the same concentration and temperature. Notably, a comparable response (~300%) is achieved at a reduced temperature of 140 \u00b0C, indicating the potential for low-power operation. The sensing mechanism is governed primarily by the ZnO layer, while b-Si serves as a morphological scaffold, increasing the effective surface area. These results demonstrate that ZnO-coated b-Si nanostructures represent a promising platform for high-performance NO2 sensing and offer strong potential for integration with silicon-based microelectronic technologies.<\/jats:p>","DOI":"10.3390\/nano16070427","type":"journal-article","created":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T08:08:34Z","timestamp":1775030914000},"page":"427","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Highly Sensitive NO2 Gas Sensors Based on ZnO-Coated Black Silicon Nanostructures"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9245-6758","authenticated-orcid":false,"given":"Gagik","family":"Ayvazyan","sequence":"first","affiliation":[{"name":"Optoelectronics Laboratory, National Polytechnic University of Armenia, 105, Teryan Street, Yerevan 0009, Armenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Lakhoyan","sequence":"additional","affiliation":[{"name":"Optoelectronics Laboratory, National Polytechnic University of Armenia, 105, Teryan Street, Yerevan 0009, Armenia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alina","family":"Semchenko","sequence":"additional","affiliation":[{"name":"Department of Physics and Information Technologies, Skorina Gomel State University, 104, Sovetskaya, 246019 Gomel, Belarus"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vazgen","family":"Melikyan","sequence":"additional","affiliation":[{"name":"Optoelectronics Laboratory, National Polytechnic University of Armenia, 105, Teryan Street, Yerevan 0009, Armenia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"140006","DOI":"10.1016\/j.colsurfa.2026.140006","article-title":"Atomic-level sensing mechanism of Rh-doped MoS2\u2013WS2 heterojunction towards dissolved H2, C2H2, and C2H4 in transformer oil: A first-principles study","volume":"738","author":"Wu","year":"2026","journal-title":"Colloids Surf. 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