{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T09:38:10Z","timestamp":1786700290416,"version":"build-2736575974"},"reference-count":53,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"State Key Laboratory of Advanced Fiber Materials at Donghua University in China","award":["KF2603"],"award-info":[{"award-number":["KF2603"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Flexible strain sensors require both a responsive conductive network and a mechanically compliant supporting structure. In this study, a sandwich-structured carbon nanotube (CNT)\/graphene\u2013thermoplastic polyurethane (TPU) nanofiber strain sensor was fabricated by electrospinning, spray-coating, pre-stretching, and hot-pressing. Field-emission scanning electron microscopy was used to examine the nanofiber and coated-fiber morphology, while energy-dispersive X-ray spectroscopy was used only to describe elemental distribution. The electrical response was quantitatively evaluated under tensile deformation. The sensor exhibited piecewise gauge factors of approximately 47.3, 269.6, and 613.8 over strain ranges of 0\u201320%, 20\u201345%, and 45\u201360%, respectively. The response and recovery times were approximately 120 and 180 ms, and the electrical response remained observable over 5000 loading\u2013unloading cycles at 20% strain. Qualitative demonstrations involving finger-bending, elbow-bending, pulse, grasping, walking, and repeated pressing produced distinguishable resistance-time patterns. These results indicate the potential of the CNT\/graphene\u2013TPU device for wearable deformation monitoring.<\/jats:p>","DOI":"10.3390\/mi17080959","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T09:04:01Z","timestamp":1786698241000},"page":"959","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Performance Evaluation of a Sandwich-Structured CNT\/Graphene\u2013TPU Nanofiber Strain Sensor for Wearable Deformation Monitoring"],"prefix":"10.3390","volume":"17","author":[{"given":"Heng","family":"Su","sequence":"first","affiliation":[{"name":"School of Art and Design, Shanghai Dianji University, Shanghai 201306, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9361-222X","authenticated-orcid":false,"given":"Shengbin","family":"Cao","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Shanghai Dianji University, Shanghai 201306, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7149-3802","authenticated-orcid":false,"given":"Xue","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Donghua University, Shanghai 201620, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zeyu","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaosong","family":"Liu","sequence":"additional","affiliation":[{"name":"Oxford Suzhou Centre for Advanced Research, Suzhou 215123, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"139706","DOI":"10.1016\/j.jcis.2025.139706","article-title":"Enhanced-performance flexible pressure sensors enabled by synergistic effect of hierarchical porous structures for motion sensing and deep learning-assisted speech recognition","volume":"707","author":"He","year":"2026","journal-title":"J. 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