{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T23:18:37Z","timestamp":1781306317848,"version":"3.54.1"},"reference-count":36,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,2,25]],"date-time":"2022-02-25T00:00:00Z","timestamp":1645747200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Fe-based metallo-supramolecular polymer (polyFe), composed of Fe(II) ions and bis(terpyridyl)benzene, is known as a good electrochromic (EC) material. For the first time, to improve the EC properties, we prepared nanocomposites comprising polyFe and a layered inorganic\u2013imidazoline covalently bonded hybrid (LIIm) by simply mixing them in methanol and then examined the effect of the nanocomposition on EC properties. The obtained blue\/purple-colored composites (polyFe\/LIIm composites) were demonstrated by scanning electron microscopy (SEM) to comprise a structure of LIIm nanoparticles coated with amorphous polyFe. Interestingly, X-ray diffraction (XRD) measurements suggested that there was no intercalation of polyFe in the interlayer space of LIIm. Ultraviolet-visible (UV-vis) spectroscopy measurements demonstrated that light absorption close to 600 nm was attributed to metal-to-ligand charge transfer (MLCT) from the Fe(II) ion to the bisterpyridine ligand and was influenced by LIIm in the composites. The composites exhibited a pair of redox waves, assigned to the redox between Fe(II) and Fe(III), in the cyclic voltammograms; moreover, the composites were estimated to be diffusion controlled. Thin composite films demonstrated reversible EC changes, triggered by the redox reaction of the metal. Furthermore, the results show that the nano-scale composition of the metallo-supramolecular polymers with LIIm can effectively improve the memory properties without reducing the contrast in transmittance (\u0394T) of 70\u201376% in EC changes after applying 1.2 V vs. Ag\/Ag+. The EC properties varied with varying ratios (3\/0.1, 0.5, 1, and 5) of the polyFe\/LIIm, and the ratio of 3\/1 exhibited the longest memory and largest MLCT absorption peak among composites. The results show that the polyFe\/LIIm composites are useful EC materials for dimming glass applications, such as smart windows.<\/jats:p>","DOI":"10.3390\/polym14050915","type":"journal-article","created":{"date-parts":[[2022,2,27]],"date-time":"2022-02-27T20:48:33Z","timestamp":1645994913000},"page":"915","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Nanocomposites of Fe(II)-Based Metallo-Supramolecular Polymer and a Layered Inorganic\u2013Organic Hybrid for Improved Electrochromic Materials"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7827-7665","authenticated-orcid":false,"given":"Kazuko","family":"Fujii","sequence":"first","affiliation":[{"name":"Electronic Functional Macromolecules Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4784-9530","authenticated-orcid":false,"given":"Manas Kumar","family":"Bera","sequence":"additional","affiliation":[{"name":"Electronic Functional Macromolecules Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dines Chandra","family":"Santra","sequence":"additional","affiliation":[{"name":"Electronic Functional Macromolecules Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9877-1134","authenticated-orcid":false,"given":"Masayoshi","family":"Higuchi","sequence":"additional","affiliation":[{"name":"Electronic Functional Macromolecules Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"192","DOI":"10.1364\/AO.8.S1.000192","article-title":"A novel electrographic system","volume":"3","author":"Deb","year":"1969","journal-title":"Appl. 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