{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,30]],"date-time":"2026-10-30T12:52:02Z","timestamp":1793364722790,"version":"4.5.0"},"reference-count":36,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,17]],"date-time":"2025-12-17T00:00:00Z","timestamp":1765929600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012511","name":"Escuela Polit\u00e9cnica Nacional","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100012511","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study investigates the effect of laser power, focal length, and number of passes on the fabrication of graphene-based strain sensors using a 450 nm diode laser at the upper limit of the UV spectrum. Polyimide substrates were irradiated to produce laser-induced graphene, and the resulting sensors were evaluated under three-point bending tests. The main requirements for deformation sensors\u2014adequate conductivity, mechanical stability under bending, and high sensitivity (gauge factor)\u2014were assessed through morphological analysis by SEM, Raman spectroscopy, and electrical characterization using the Van der Pauw method. The results indicate that laser power is the critical factor influencing graphene quality and sensor performance, while focal length has a negligible effect and additional passes reduce material quality and sensitivity. Overall, this work demonstrates the feasibility of producing functional, low-cost graphene strain sensors with a commercial diode laser, offering a scalable and affordable alternative for sensor fabrication.<\/jats:p>","DOI":"10.3390\/s25247641","type":"journal-article","created":{"date-parts":[[2025,12,17]],"date-time":"2025-12-17T10:41:23Z","timestamp":1765968083000},"page":"7641","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Laser-Induced Graphene on Polyimide: Material Characterization Toward Strain-Sensing Applications"],"prefix":"10.3390","volume":"25","author":[{"given":"Yessenia Ibeth","family":"Paucar","sequence":"first","affiliation":[{"name":"Materials Department, Faculty of Mechanical Engineering, Escuela Polit\u00e9cnica Nacional, Ladr\u00f3n de Guevara E11-253, P.O. Box 17-01-2759, Quito 170525, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6989-0126","authenticated-orcid":false,"given":"Fernando","family":"Pantoja-Su\u00e1rez","sequence":"additional","affiliation":[{"name":"Materials Department, Faculty of Mechanical Engineering, Escuela Polit\u00e9cnica Nacional, Ladr\u00f3n de Guevara E11-253, P.O. Box 17-01-2759, Quito 170525, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9694-3729","authenticated-orcid":false,"given":"Enric","family":"Bertran-Serra","sequence":"additional","affiliation":[{"name":"ENPHOCAMAT (FEMAN) Group, Deparment of Applied Physics, Universitat de Barcelona, Mart\u00ed i Franqu\u00eas 1, 8028 Barcelona, Spain"},{"name":"Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, 08028 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-9327-3522","authenticated-orcid":false,"given":"Fernando","family":"S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Materials Department, Faculty of Mechanical Engineering, Escuela Polit\u00e9cnica Nacional, Ladr\u00f3n de Guevara E11-253, P.O. Box 17-01-2759, Quito 170525, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-5950-7307","authenticated-orcid":false,"given":"Katherine","family":"Moreno","sequence":"additional","affiliation":[{"name":"Department of Extractive Metallurgy, Escuela Polit\u00e9cnica Nacional, Ladr\u00f3n de Guevara E11-253, P.O. Box 17-01-2759, Quito 170525, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Holkar, C.R., Jain, S.S., Jadhav, A.J., and Pinjari, D.V. (2018). Scale-Up Technologies for Advanced Nanomaterials for Green Energy: Feasibilities and Challenges. 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