{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T04:33:59Z","timestamp":1772166839775,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,9,14]],"date-time":"2022-09-14T00:00:00Z","timestamp":1663113600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Toubkal 2017 funding program (Programme Hubert Curien)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>In this work, we investigated the orientation and the polarization of ZnO nanoparticles, which serve as building blocks of highly monodisperse microspheres, using a droplet microfluidic-assisted synthesis method. We observe, for the first time, a square lattice organization of liquid microdroplets, in a steady state, at the oil\/water interface. Such square organization reveals clearly a dipolar organization of ZnO nanoparticles at the surfaces of droplets at the early stage of ZnO nanocrystal aggregation and microsphere formation. We discuss different models of organization of ZnO nanoparticles and show that the well-known tip-streaming effect in droplets in microfluidics explains the reason for the obtained dipolar droplets. The square organization is illustrated and explained.<\/jats:p>","DOI":"10.3390\/mi13091522","type":"journal-article","created":{"date-parts":[[2022,9,14]],"date-time":"2022-09-14T23:16:36Z","timestamp":1663197396000},"page":"1522","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Hierarchical Self-Assembly of Dipolar ZnO Nanoparticles and Microdroplets"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5368-1741","authenticated-orcid":false,"given":"Najla","family":"Ghifari","sequence":"first","affiliation":[{"name":"Laboratoire Lumi\u00e8re Mati\u00e8re et Interfaces (LUMIN), UMR 9024, Ecole Normale Sup\u00e9rieure Paris Saclay, CentraleSup\u00e9lec, CNRS, Universit\u00e9 Paris-Saclay, 4 Avenue des Sciences, 91190 Gif-sur-Yvette, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8876-9361","authenticated-orcid":false,"given":"Rachid","family":"Bennacer","sequence":"additional","affiliation":[{"name":"ENS Paris-Saclay, CNRS, LMPS, Universit\u00e9 Paris-Saclay, 91190 Gif-sur-Yvette, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3113-316X","authenticated-orcid":false,"given":"Adil","family":"Chahboun","sequence":"additional","affiliation":[{"name":"Laboratoire des Couches Minces et Nanomat\u00e9riaux (CMN), FST Tanger, Universit\u00e9 Abdelmalek Essaadi, BP 416, Tangier 90000, Morocco"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3324-2300","authenticated-orcid":false,"given":"Abdel I.","family":"El Abed","sequence":"additional","affiliation":[{"name":"Laboratoire Lumi\u00e8re Mati\u00e8re et Interfaces (LUMIN), UMR 9024, Ecole Normale Sup\u00e9rieure Paris Saclay, CentraleSup\u00e9lec, CNRS, Universit\u00e9 Paris-Saclay, 4 Avenue des Sciences, 91190 Gif-sur-Yvette, France"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"C\u00f6elfen, H., and Antonietti, M. 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