{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T09:11:22Z","timestamp":1773306682672,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T00:00:00Z","timestamp":1773187200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Reliable detection of microplastics by surface-enhanced Raman scattering (SERS) is often hindered by poor particle\u2013substrate contact and limited access to plasmonic hotspots on conventional planar substrates optimized for molecular adsorption. Here, we report a rapid microwave-assisted carbothermal shock strategy to fabricate silver nanoparticle-decorated electrospun carbon fibers (AgNPs@ECF) as a three-dimensional plasmonic platform tailored for solid microplastic sensing. Localized microwave-induced heating in a mixed ethanol\u2013hexane system enables Ag nanoparticle nucleation and anchoring on conductive carbon fibers within 45 s, yielding a mechanically compliant, junction-rich architecture without chemical reductants or vacuum processing. The AgNPs@ECF composite was evaluated using morphologically weathered polystyrene (PS) and polyethylene terephthalate (PET) microplastics, along with size-controlled PS bead standards ranging from ~50 nm to 45 \u03bcm. Across these models, SERS response is governed primarily by particle\u2013substrate contact geometry and near-field accessibility rather than polymer type. The strongest enhancement occurs in the sub-micrometer regime, where particles can engage multiple AgNP-decorated fiber junctions, while ultrasmall and large, smooth particles show reduced enhancement due to limited contact or rapid field decay. Spatially resolved Raman mapping and finite-difference time-domain simulations support a contact-dominated enhancement mechanism, revealing localized field confinement at particle\u2013fiber interfaces. These results establish the design principles for three-dimensional SERS substrates targeting heterogeneous solid particulates, demonstrating that contact-accessible plasmonic architectures are critical for reliable microplastic detection under realistic solid-particle measurement conditions.<\/jats:p>","DOI":"10.3390\/ma19061074","type":"journal-article","created":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T14:43:18Z","timestamp":1773240198000},"page":"1074","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Contact-Accessible Silver Nanoparticle-Decorated Electrospun Carbon Fibers for Microplastics Detection by SERS"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6565-3131","authenticated-orcid":false,"given":"FNU","family":"Joshua","sequence":"first","affiliation":[{"name":"NanoScience Technology Center, University of Central Florida, Orlando, FL 32826, USA"},{"name":"Department of Chemistry, University of Central Florida, Orlando, FL 32826, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuen Yee","family":"Li Sip","sequence":"additional","affiliation":[{"name":"NanoScience Technology Center, University of Central Florida, Orlando, FL 32826, USA"},{"name":"Department of Materials Science and Engineering, University of Central Florida, Orlando, FL 32816, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aritra","family":"Biswas","sequence":"additional","affiliation":[{"name":"NanoScience Technology Center, University of Central Florida, Orlando, FL 32826, USA"},{"name":"College of Optics and Photonics, University of Central Florida, Orlando, FL 32816, USA"},{"name":"Department of Physics, University of Central Florida, Orlando, FL 32826, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Violette","family":"Gray","sequence":"additional","affiliation":[{"name":"NanoScience Technology Center, University of Central Florida, Orlando, FL 32826, USA"},{"name":"Department of Mechanical Engineering, Daytona State College, Daytona Beach, FL 32114, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Debashis","family":"Chanda","sequence":"additional","affiliation":[{"name":"NanoScience Technology Center, University of Central Florida, Orlando, FL 32826, USA"},{"name":"College of Optics and Photonics, University of Central Florida, Orlando, FL 32816, USA"},{"name":"Department of Physics, University of Central Florida, Orlando, FL 32826, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3886-2154","authenticated-orcid":false,"given":"Lei","family":"Zhai","sequence":"additional","affiliation":[{"name":"NanoScience Technology Center, University of Central Florida, Orlando, FL 32826, USA"},{"name":"Department of Chemistry, University of Central Florida, Orlando, FL 32826, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Busch, S.J., Craig, C.A., Wayles, J., Sailor-Tynes, T., Dark, E., Sweat, L.H., Fox, D.W., Zhai, L., and Walters, L.J. 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