{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T21:10:35Z","timestamp":1778274635508,"version":"3.51.4"},"reference-count":21,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T00:00:00Z","timestamp":1778112000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundamental Research Funds for the Central Universities of Ministry of Education of China","award":["D5000240188"],"award-info":[{"award-number":["D5000240188"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This study successfully developed an efficient one-dimensional confinement strategy to encapsulate polyoxometalate NiMo6 clusters densely and uniformly within the cavities of a single-walled carbon nanotube (SWCNT), constructing a unique core\u2013shell NiMo6@SWCNT composite electrocatalyst. Comprehensive characterization including high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible absorption spectroscopy (UV-Vis) systematically confirmed the uniform dispersion and structural integrity of NiMo6 within the SWCNT channels. Key evidence encompasses: (1) EDS elemental mapping revealing high co-localization of Ni\/Mo signals inside the lumens; (2) transmission electron microscopy (TEM) images confirming the effectiveness of the filling process. The composite achieved an exceptionally low overpotential of 308 mV to drive a current density of 10 mA cm\u22122 (significantly outperforming pure NiMo6 at 365 mV and pristine SWCNT at 519 mV), exhibited a remarkably low Tafel slope of 96.64 mV dec\u22121, possessed a high electrochemical active surface area (10.75 mF cm\u22122), and very low charge transfer resistance. Critically, it showed negligible current density decay during prolonged chronoamperometric operation over 35,000 s (&gt;9.7 h). This work not only validates the confined encapsulation as a viable strategy for fabricating highly active polyoxometalate\/carbon composites, but also elucidates that the performance enhancement stems from a \u201ctriple synergy\u201d: the intrinsic catalytic activity of NiMo6, the highly conductive\/mass-transport network provided by SWCNT, and the synergistic effects arising from the confined interface\u2014namely stress regulation and electronic coupling. This insight provides a novel perspective for designing high-performance non-precious metal electrocatalysts.<\/jats:p>","DOI":"10.3390\/mi17050583","type":"journal-article","created":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T20:11:13Z","timestamp":1778271073000},"page":"583","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Rational Confinement of NiMo6 Polyoxometalates in a Single-Walled Carbon Nanotube: A High-Filling-Ratio Strategy for Enhanced Electrochemical Activity"],"prefix":"10.3390","volume":"17","author":[{"given":"Kai","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Textile Science and Engineering, Wuhan Textile University, Yangguang Road 1, Wuhan 430200, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zeling","family":"Yang","sequence":"additional","affiliation":[{"name":"Institute of Materials Science and Devices, School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chengxu","family":"Zhou","sequence":"additional","affiliation":[{"name":"Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Materials Science and Engineering, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinwang","family":"Cao","sequence":"additional","affiliation":[{"name":"School of Textile Science and Engineering, Wuhan Textile University, Yangguang Road 1, Wuhan 430200, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8261-875X","authenticated-orcid":false,"given":"Xiyuan","family":"Feng","sequence":"additional","affiliation":[{"name":"School of Microelectronics, Northwestern Polytechnical University, No. 1 Dongxiang Road, Chang\u2019an District, Xi\u2019an 710129, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Tariq, I., Asghar, M.A., Ali, A., Badshah, A., Abbas, S.M., Iqbal, W., Zubair, M., Haider, A., and Zaman, S. 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