{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T17:47:49Z","timestamp":1791222469430,"version":"4.1.0"},"reference-count":24,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T00:00:00Z","timestamp":1645574400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FICYT- Consejer\u00eda de Ciencia, Innovaci\u00f3n y Universidad - Gobierno del Principado de Asturias","award":["AYUD \/ 2021 \/ 57246"],"award-info":[{"award-number":["AYUD \/ 2021 \/ 57246"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Solid-state lighting (SSL) sources based on light-emitting diodes represent the new generation of highly efficient illumination systems that significantly impact energy-saving. The development of white light-emitting diodes (WLEDs) with a combination of high color rendering index (CRI) and high deep-red color rendering R9 is an important challenge in the field of solid-state lighting. On the other hand, most WLEDs use rare-earth inorganic luminescent materials. The annual demand for rare-earth metals has doubled to 125,000 tons in 15 years, and the demand is projected to reach 315,000 tons in 2030. The explosion in demand for these materials, combined with a monopolistic supply source, represents a real risk for the development of WLEDs in the next few years. Luminescent organic materials are a relevant and promising alternative. Here, we report a WLED with a very high CRI of 95.7 and R9 of 78.7, obtained using a combination of a blue LED chip (excitation source) and two organic luminescent dyes (Coumarin 6 and Lumogen Red) acting as spectral converters in a multilayer remote phosphor configuration. To the best of our knowledge, this is the first rare-earth-free WLED with such high values of CRI and R9.<\/jats:p>","DOI":"10.3390\/ma15051680","type":"journal-article","created":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T22:54:02Z","timestamp":1645656842000},"page":"1680","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Sunlike White Light-Emitting Diodes Based on Rare-Earth-Free Luminescent Materials"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0583-3610","authenticated-orcid":false,"given":"Amador","family":"Men\u00e9ndez-Vel\u00e1zquez","sequence":"first","affiliation":[{"name":"Photoactive Materials Research Unit, IDONIAL Technology Center, 33417 Avil\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dolores","family":"Morales","sequence":"additional","affiliation":[{"name":"Photoactive Materials Research Unit, IDONIAL Technology Center, 33417 Avil\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana Bel\u00e9n","family":"Garc\u00eda-Delgado","sequence":"additional","affiliation":[{"name":"Photoactive Materials Research Unit, IDONIAL Technology Center, 33417 Avil\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Nakamura, S., Pearton, S., and Fasol, G. 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