{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:09:14Z","timestamp":1785434954563,"version":"3.56.0"},"reference-count":45,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T00:00:00Z","timestamp":1785110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University Kassel","award":["1.10.01\/FF 4"],"award-info":[{"award-number":["1.10.01\/FF 4"]}]},{"award":["1.10.01\/FF 4"],"award-info":[{"award-number":["1.10.01\/FF 4"]}],"id":[{"id":"https:\/\/ror.org\/04zc7p361","id-type":"ROR","asserted-by":"publisher"}]},{"name":"DFG project","award":["430159793"],"award-info":[{"award-number":["430159793"]}]},{"DOI":"10.13039\/501100001659","name":"DFG-Heisenberg","doi-asserted-by":"publisher","award":["505496601"],"award-info":[{"award-number":["505496601"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"European Union","doi-asserted-by":"publisher","award":["GA-101135196"],"award-info":[{"award-number":["GA-101135196"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"award":["GA-101135196"],"award-info":[{"award-number":["GA-101135196"]}],"id":[{"id":"https:\/\/ror.org\/019w4f821","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001823","name":"Ministry of Education Youth and Sports","doi-asserted-by":"crossref","award":["LL2101"],"award-info":[{"award-number":["LL2101"]}],"id":[{"id":"10.13039\/501100001823","id-type":"DOI","asserted-by":"crossref"}]},{"award":["LL2101"],"award-info":[{"award-number":["LL2101"]}],"id":[{"id":"https:\/\/ror.org\/037n8p820","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Van der Waals indium selenide is a promising material for next-generation optoelectronics due to its thickness-dependent band structure and high carrier mobility. Here, we investigate the optical properties of size-selected liquid-phase exfoliated \u03b3-InSe nanosheets. The dispersions, composed of flakes with lateral dimensions below 100 nm, exhibit pronounced structural disorder and size-dependent optical behavior. Absorbance spectroscopy reveals systematic changes across size-selected fractions, enabling the extraction of quantitative metrics for estimating nanosheet lateral size and layers number. In addition, stability studies demonstrate significant degradation under ambient conditions, which is accelerated at elevated temperatures. Photoluminescence measurements on nanosheets exfoliated under inert conditions show broad, asymmetric emission with a clear blue-shift for smaller flakes, reflecting quantum confinement and dielectric screening effects. The emission characteristics further indicate a dominant contribution from localized states associated with disorder. These findings provide insight into the structure\u2013property relationships in liquid-phase exfoliated \u03b3-InSe and highlight its potential for solution-processed optoelectronic applications.<\/jats:p>","DOI":"10.3390\/nano16150925","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T16:11:56Z","timestamp":1785168716000},"page":"925","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Probing the Optical Properties of Size-Selected Liquid-Phase Exfoliated \u03b3-Indium Selenide"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5653-6416","authenticated-orcid":false,"given":"Mikhail","family":"Kochiev","sequence":"first","affiliation":[{"name":"Institute of Nanostructure Technologies and Analytics (INA), Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin R.","family":"Synnatschke","sequence":"additional","affiliation":[{"name":"Center for Advancing Electronics Dresden (CfAED), Faculty of Chemistry and Food Chemistry, Technische Universit\u00e4t Dresden, 01062 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-1959-3172","authenticated-orcid":false,"given":"Sabrina","family":"Steffens","sequence":"additional","affiliation":[{"name":"Institute of Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tim","family":"Nowack","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zden\u00eak","family":"Sofer","sequence":"additional","affiliation":[{"name":"Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4154-0439","authenticated-orcid":false,"given":"Claudia","family":"Backes","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4756-3818","authenticated-orcid":false,"given":"Mohamed","family":"Benyoucef","sequence":"additional","affiliation":[{"name":"Institute of Nanostructure Technologies and Analytics (INA), Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1038\/nnano.2016.242","article-title":"High Electron Mobility, Quantum Hall Effect and Anomalous Optical Response in Atomically Thin InSe","volume":"12","author":"Bandurin","year":"2017","journal-title":"Nat. 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