{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T15:41:17Z","timestamp":1787067677291,"version":"build-2736575974"},"reference-count":35,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,10,25]],"date-time":"2024-10-25T00:00:00Z","timestamp":1729814400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Soonchunhyang University Research Fund","award":["P0012453"],"award-info":[{"award-number":["P0012453"]}]},{"name":"Soonchunhyang University Research Fund","award":["RS-2024-00420455"],"award-info":[{"award-number":["RS-2024-00420455"]}]},{"name":"Korea Institute for Advancement of Technology (KIAT) grant funded by the Korean government (MOTIE)","award":["P0012453"],"award-info":[{"award-number":["P0012453"]}]},{"name":"Korea Institute for Advancement of Technology (KIAT) grant funded by the Korean government (MOTIE)","award":["RS-2024-00420455"],"award-info":[{"award-number":["RS-2024-00420455"]}]},{"name":"MOTIE\/KEIT","award":["P0012453"],"award-info":[{"award-number":["P0012453"]}]},{"name":"MOTIE\/KEIT","award":["RS-2024-00420455"],"award-info":[{"award-number":["RS-2024-00420455"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>We developed inverted red quantum dot light-emitting diodes (QLEDs) with ZnO nanoparticles synthesized in open and closed systems. Wurtzite-structured ZnO nanoparticles were synthesized using potassium hydroxide and zinc acetate dihydrate at various temperatures in the open and closed systems. The particle size increases with increasing synthesis temperature. The ZnO nanoparticles synthesized at 50, 60, and 70 \u00b0C in the closed system have an average particle size of 3.2, 4.0, and 5.4 nm, respectively. The particle size is larger in the open system compared to the closed system as the methanol solvent evaporates during the synthesis process. The surface defect-induced emission in ZnO nanoparticles shifts to a longer wavelength and the emission intensity decreases as the synthesis temperature increases. The inverted red QLEDs were fabricated with a synthesized ZnO nanoparticle electron transport layer. The driving voltage of the inverted QLEDs decreases as the synthesis temperature increases. The current efficiency is higher in the inverted red QLEDs with the ZnO nanoparticles synthesized in the closed system compared to the devices with the nanoparticles synthesized in the open system. The device with the ZnO nanoparticles synthesized at 60 \u00b0C in the closed system exhibits the maximum current efficiency of 5.8 cd\/A.<\/jats:p>","DOI":"10.3390\/mi15111297","type":"journal-article","created":{"date-parts":[[2024,10,25]],"date-time":"2024-10-25T03:46:04Z","timestamp":1729827964000},"page":"1297","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Inverted Red Quantum Dot Light-Emitting Diodes with ZnO Nanoparticles Synthesized Using Zinc Acetate Dihydrate and Potassium Hydroxide in Open and Closed Systems"],"prefix":"10.3390","volume":"15","author":[{"given":"Se-Hoon","family":"Jang","sequence":"first","affiliation":[{"name":"Department of Electronic Materials, Device, and Equipment Engineering, Soonchunhyang University, Asan-si 31538, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Go-Eun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronic Materials, Device, and Equipment Engineering, Soonchunhyang University, Asan-si 31538, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sang-Uk","family":"Byun","sequence":"additional","affiliation":[{"name":"Department of Electronic Materials, Device, and Equipment Engineering, Soonchunhyang University, Asan-si 31538, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-4672-7976","authenticated-orcid":false,"given":"Kyoung-Ho","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electronic Materials, Device, and Equipment Engineering, Soonchunhyang University, Asan-si 31538, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9725-8718","authenticated-orcid":false,"given":"Dae-Gyu","family":"Moon","sequence":"additional","affiliation":[{"name":"Department of Electronic Materials, Device, and Equipment Engineering, Soonchunhyang University, Asan-si 31538, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"354","DOI":"10.1038\/370354a0","article-title":"Light-emitting diodes made from cadmium selenide nanocrystals and a semiconducting polymer","volume":"370","author":"Colvin","year":"1994","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1038\/nphoton.2012.328","article-title":"Emergence of colloidal quantum-dot light-emitting technologies","volume":"7","author":"Shirasaki","year":"2013","journal-title":"Nature Photon."},{"key":"ref_3","first-page":"640","article-title":"Semiconductor quantum dots: Technological progress and future challenges","volume":"373","author":"Arquer","year":"2021","journal-title":"Science"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"106086","DOI":"10.1016\/j.orgel.2021.106086","article-title":"A review on the electroluminescence properties of quantum-dot light-emitting diodes","volume":"90","author":"Yuan","year":"2021","journal-title":"Org. 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C"}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/15\/11\/1297\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:20:12Z","timestamp":1760113212000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/15\/11\/1297"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,10,25]]},"references-count":35,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2024,11]]}},"alternative-id":["mi15111297"],"URL":"https:\/\/doi.org\/10.3390\/mi15111297","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,10,25]]}}}