{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:49:34Z","timestamp":1789519774094,"version":"build-2803163510"},"reference-count":52,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,8]],"date-time":"2022-12-08T00:00:00Z","timestamp":1670457600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research University Grant UKM","award":["GUP-2019-014"],"award-info":[{"award-number":["GUP-2019-014"]}]},{"name":"Research University Grant UKM","award":["UTMFR-22H16"],"award-info":[{"award-number":["UTMFR-22H16"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Detection of sub-ppm acetic acid (CH3COOH) is in demand for environmental gas monitoring. In this article, we propose a CH3COOH gas sensor based on Sn3O4 and reduced graphene oxide (RGO), where the assembly of Sn3O4-RGO nanocomposites is dependent on the synthesis method. Three nanocomposites prepared by three different synthesis methods are investigated. The optimum assembly is by hydrothermal reactions of Sn4+ salts and pre-reduced RGO (designated as RS nanocomposite). Raman spectra verified the fingerprint of RGO in the synthesized RS nanocomposite. The Sn3O4 planes of (111), (210), (130), (13\u00af2) are observed from the X-ray diffractogram, and its average crystallite size is 3.94 nm. X-ray photoelectron spectroscopy on Sn3d and O1s spectra confirm the stoichiometry of Sn3O4 with Sn:O ratio = 0.76. Sn3O4-RGO-RS exhibits the highest response of 74% and 4% at 2 and 0.3 ppm, respectively. The sensitivity within sub-ppm CH3COOH is 64%\/ppm. Its superior sensing performance is owing to the embedded and uniformly wrapped Sn3O4 nanoparticles on RGO sheets. This allows a massive relative change in electron concentration at the Sn3O4-RGO heterojunction during the on\/off exposure of CH3COOH. Additionally, the operation is performed at room temperature, possesses good repeatability, and consumes only ~4 \u00b5W, and is a step closer to the development of a commercial CH3COOH sensor.<\/jats:p>","DOI":"10.3390\/molecules27248707","type":"journal-article","created":{"date-parts":[[2022,12,9]],"date-time":"2022-12-09T03:23:49Z","timestamp":1670556229000},"page":"8707","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Highly Sensitive Sub-ppm CH3COOH Detection by Improved Assembly of Sn3O4-RGO Nanocomposite"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8271-5066","authenticated-orcid":false,"given":"Norazreen Abd","family":"Aziz","sequence":"first","affiliation":[{"name":"Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia"},{"name":"MIMOS Semiconductor (M) Sdn Bhd, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6911-0716","authenticated-orcid":false,"given":"Mohd Faizol","family":"Abdullah","sequence":"additional","affiliation":[{"name":"MIMOS Semiconductor (M) Sdn Bhd, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siti Aishah Mohamad","family":"Badaruddin","sequence":"additional","affiliation":[{"name":"MIMOS Semiconductor (M) Sdn Bhd, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohd Rofei Mat","family":"Hussin","sequence":"additional","affiliation":[{"name":"MIMOS Semiconductor (M) Sdn Bhd, Technology Park Malaysia, Kuala Lumpur 57000, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdul Manaf","family":"Hashim","sequence":"additional","affiliation":[{"name":"Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, Kuala Lumpur 54100, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Khan, M.A.H., Rao, M.V., and Li, Q. 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