{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T04:50:05Z","timestamp":1791521405413,"version":"4.3.4"},"reference-count":26,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002461","name":"Chungbuk National University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002461","id-type":"DOI","asserted-by":"publisher"}]},{"id":[{"id":"https:\/\/ror.org\/02wnxgj78","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001459","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2026-RISE-11-014-03"],"award-info":[{"award-number":["2026-RISE-11-014-03"]}],"id":[{"id":"10.13039\/501100001459","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chungcheongbuk-do","award":["2026-RISE-11-014-03"],"award-info":[{"award-number":["2026-RISE-11-014-03"]}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2026-25479266"],"award-info":[{"award-number":["RS-2026-25479266"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"award":["RS-2026-25479266"],"award-info":[{"award-number":["RS-2026-25479266"]}],"id":[{"id":"https:\/\/ror.org\/013aysd81","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Laser-induced graphene (LIG) is a promising porous carbon electrode for flexible microsupercapacitors (MSCs), and defocusing is an established means of tuning its morphology. Here, a defocusing series was evaluated as a complete process-to-device chain with the CO2 laser power and scan speed fixed at 5.0 W and 46 mm s\u22121. A polyimide substrate was positioned 0\u20133 mm below the focal plane to produce laser-induced graphene fibers (LIGFs), LIG-1, LIG-2, and LIG-3. Increasing the defocusing distance lowered the peak fluence per pulse from 16.7 to 2.1 J cm\u22122, transforming a fibrous network into porous LIG, an open-cell-like network, and a film whose smooth, oxygen-rich surface skin covered a porous interior. LIG-2 showed the lowest sheet resistance (15.3 \u2126 sq\u22121), ID\/IG ratio (0.29), and equivalent series resistance (78 \u2126), delivering 2.88 mF cm\u22122 at 0.05 mA cm\u22122 and 97.4% retention after 2000 cycles. LIGF showed the lowest contact angle (12.1\u00b0), retained 57.3% of its capacitance at 0.25 mA cm\u22122, and surpassed LIG-2 at \u22650.10 mA cm\u22122. Both electrodes retained their cyclic voltammetry (CV) response under a single 180\u00b0 bend. Thus, substrate-height adjustment tunes LIG morphology and rate-dependent MSC performance without changing laser power or scan speed.<\/jats:p>","DOI":"10.3390\/polym18192377","type":"journal-article","created":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T15:14:37Z","timestamp":1790694877000},"page":"2377","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Defocusing-Controlled Morphology and Electrochemical Performance of Laser-Induced Graphene Electrodes for Microsupercapacitors"],"prefix":"10.3390","volume":"18","author":[{"given":"Seon Jong","family":"Yu","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Da Hwan","family":"Yu","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mun Jeong","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9381-4908","authenticated-orcid":false,"given":"Inhwan","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"},{"name":"Department of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jungho","family":"Cho","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"},{"name":"Department of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3151-8585","authenticated-orcid":false,"given":"Hyoryung","family":"Nam","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Daegu Catholic University School of Medicine, 33 Duryugongwon-ro 17-gil, Nam-gu, Daegu 42472, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3178-4947","authenticated-orcid":false,"given":"Geon Hwee","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"},{"name":"Department of Mechanical Engineering, Chungbuk National University (CBNU), 1, Chungdae-ro, Seowon-gu, Cheongju-si 28644, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1038\/nnano.2016.196","article-title":"Microsupercapacitors as Miniaturized Energy-Storage Components for on-Chip Electronics","volume":"12","author":"Kyeremateng","year":"2017","journal-title":"Nat. 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