{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:40:33Z","timestamp":1785404433397,"version":"3.56.0"},"reference-count":39,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005645","name":"Vietnamese Ministry of Education and Training","doi-asserted-by":"publisher","award":["B2024-SPH-09"],"award-info":[{"award-number":["B2024-SPH-09"]}],"id":[{"id":"10.13039\/501100005645","id-type":"DOI","asserted-by":"publisher"}]},{"award":["B2024-SPH-09"],"award-info":[{"award-number":["B2024-SPH-09"]}],"id":[{"id":"https:\/\/ror.org\/00drv3378","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Transition-metal sulfides are promising electrode materials for high-performance supercapacitors but are often limited by poor conductivity, particle agglomeration, and insufficient active sites. Herein, Co-doped NiS2 with tunable sulfur vacancies was directly grown on flexible carbon cloth via a facile one-step solvothermal method by systematically controlling sulfur source ratio, Ni:Co ratio, temperature, and reaction time. Structural analyses reveal that the optimized conditions of S:(Ni + Co) = 3:1, Ni:Co = 2:1, 160 \u00b0C, and 15 h promote the formation of phase-pure Co-doped NiS2 hierarchical microspheres with enhanced crystallinity and abundant active sites from the synergistic interaction between Ni and Co. Consequently, the optimized electrode delivers an impressive capacitance of 1296 F g\u22121 at a current density of 1 A g\u22121, along with excellent rate performance, retaining more than 88% of its capacitance after 1500 charge\/discharge cycles at current densities ranging from 2 to 20 A g\u22121. This work highlights the critical role of synthesis parameter engineering in regulating defect chemistry, structure, and electrochemical performance in advanced energy storage applications.<\/jats:p>","DOI":"10.3390\/ma19122651","type":"journal-article","created":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T08:19:52Z","timestamp":1782202792000},"page":"2651","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Synergistic Regulation of Composition and Growth Kinetics in Cobalt-Doped Nickel Sulfides for High-Performance Pseudocapacitors"],"prefix":"10.3390","volume":"19","author":[{"given":"Hung Nguyen","family":"Dinh","sequence":"first","affiliation":[{"name":"Faculty of Chemistry, Hanoi National University of Education, Hanoi City 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cu Dang","family":"Van","sequence":"additional","affiliation":[{"name":"Vietnam-Korea Institute of Science and Technology, Hanoi City 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6597-7742","authenticated-orcid":false,"given":"Thu Thuy","family":"Luong Thi","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry, Hanoi National University of Education, Hanoi City 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0952-0144","authenticated-orcid":false,"given":"Khu","family":"Le Van","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry, Hanoi National University of Education, Hanoi City 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100229","DOI":"10.1016\/j.mne.2023.100229","article-title":"Supercapacitors for renewable energy applications: A review","volume":"21","author":"Zhang","year":"2023","journal-title":"Micro Nano Eng."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Malik, F.H., Hussain, G.A., Alsmadi, Y.M.S., Haider, Z.M., Mansoor, W., and Lehtonen, M. 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