{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T08:44:21Z","timestamp":1787906661881,"version":"build-2784847793"},"reference-count":33,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2025,7,9]],"date-time":"2025-07-09T00:00:00Z","timestamp":1752019200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the MUR project\u2019s \u201cECOTEC\u2013Smart and eco-sustainable fibres and tissues for technical clothing and high fashion\u201d","award":["PON ARS01_00951_V0584, D.D.n. 2051 del 02\/08\/2018"],"award-info":[{"award-number":["PON ARS01_00951_V0584, D.D.n. 2051 del 02\/08\/2018"]}]},{"name":"the MUR project\u2019s \u201cECOTEC\u2013Smart and eco-sustainable fibres and tissues for technical clothing and high fashion\u201d","award":["PNC0000007"],"award-info":[{"award-number":["PNC0000007"]}]},{"name":"the MUR project\u2019s \u201cECOTEC\u2013Smart and eco-sustainable fibres and tissues for technical clothing and high fashion\u201d","award":["CUP B53C22006960001"],"award-info":[{"award-number":["CUP B53C22006960001"]}]},{"name":"the MUR project\u2019s \u201cECOTEC\u2013Smart and eco-sustainable fibres and tissues for technical clothing and high fashion\u201d","award":["I-PHOQS, N. 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IR0000016"]}]},{"name":"the PNRR MUR Project\u2019s \u201cIntegrated Infra-structure Initiative in Photonic and Quantum Sciences\u201d","award":["PON ARS01_00951_V0584, D.D.n. 2051 del 02\/08\/2018"],"award-info":[{"award-number":["PON ARS01_00951_V0584, D.D.n. 2051 del 02\/08\/2018"]}]},{"name":"the PNRR MUR Project\u2019s \u201cIntegrated Infra-structure Initiative in Photonic and Quantum Sciences\u201d","award":["PNC0000007"],"award-info":[{"award-number":["PNC0000007"]}]},{"name":"the PNRR MUR Project\u2019s \u201cIntegrated Infra-structure Initiative in Photonic and Quantum Sciences\u201d","award":["CUP B53C22006960001"],"award-info":[{"award-number":["CUP B53C22006960001"]}]},{"name":"the PNRR MUR Project\u2019s \u201cIntegrated Infra-structure Initiative in Photonic and Quantum Sciences\u201d","award":["I-PHOQS, N. IR0000016"],"award-info":[{"award-number":["I-PHOQS, N. IR0000016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The fabrication of high-performance organic optoelectronic devices using solution-based techniques, in particular inkjet printing, is both a desirable and challenging goal. Organic light-emitting diodes (OLEDs) are multilayer devices that have demonstrated great potential in display applications, with ongoing efforts aimed at extending their use to the lighting sector. A key objective in this context is the reduction in production costs, for which printing techniques offer a promising pathway. The main obstacle to fully printed OLEDs lies in the difficulty of depositing new layers onto pre-existing ones while maintaining high film quality and avoiding damage to the underlying layers. In a bottom-emitting OLED, the electron transport layer (ETL) is the final organic layer to be deposited, making its printing particularly challenging, a process for which only a few successful examples have been reported. In this work, we report on the optimization of a 2,2\u2032,2\u2033-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi)-based ink formulation for ETL printing on an emitting layer composed of 5,10-Bis(4-(3,6-di-tert-butyl-9H-carbazol-9-yl)-2,6-dimethylphenyl)-5,10-dihydroboranthrene (tBuCzDBA). A specific ratio of methanol to diethyl ether was identified as the most suitable for printing the ETL without compromising the integrity of the underlying layer. The printed ETL was successfully integrated into an OLED device, which exhibited a maximum current efficiency of 6.8 cd\/A and a peak luminance of about 8700 cd\/m2. These results represent a significant step toward the development of a fully printed OLED architecture.<\/jats:p>","DOI":"10.3390\/ma18143231","type":"journal-article","created":{"date-parts":[[2025,7,10]],"date-time":"2025-07-10T09:38:27Z","timestamp":1752140307000},"page":"3231","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Optimization of Electron Transport Layer Inkjet Printing Towards Fully Solution-Processable OLEDs"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4428-4554","authenticated-orcid":false,"given":"Riccardo","family":"Manfredi","sequence":"first","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carmela Tania","family":"Prontera","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"},{"name":"Laboratory of Hydrogen and New Energy Vectors (TERIN-DEC-H2V) ENEA\u2013C.R Brindisi, S.S.7 Appia, km 713,700, 72100 Brindisi, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabrizio","family":"Mariano","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9502-8457","authenticated-orcid":false,"given":"Marco","family":"Pugliese","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1808-4778","authenticated-orcid":false,"given":"Antonio","family":"Maggiore","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandra","family":"Zizzari","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9684-7860","authenticated-orcid":false,"given":"Marco","family":"Cinquino","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iolena","family":"Tarantini","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Physics, University of Salento, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Gigli","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"},{"name":"Department of Mathematics and Physics, University of Salento, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vincenzo","family":"Maiorano","sequence":"additional","affiliation":[{"name":"CNR-NANOTEC-Institute of Nanotechnology, c\/o Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"455105","DOI":"10.1088\/1361-6463\/ab375a","article-title":"The Impact of the Deposition Process of the Emitting Layer on the Internal Structure of Organic Light-Emitting Diodes","volume":"52","author":"Maderitsch","year":"2019","journal-title":"J. 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