{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:57:43Z","timestamp":1787029063640,"version":"build-2736575974"},"reference-count":30,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T00:00:00Z","timestamp":1625011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The far ultraviolet C (UVC) light sources based on carbon nanotube (CNT) field emitters as excitation sources have become promising light sources for sterilization, disinfection, and water purification. However, the low light extraction efficiency of UVC\u2013CNT light sources still hinders the practical application of these structures. Herein, we report an optimized aluminum (Al) reflector to enhance the light extraction efficiency of UVC\u2013CNT light sources. Optical analysis of UVC-CNT light sources covered by the Al reflectors with various thicknesses ranging from 30 to 150 nm was performed to realize the optimized reflector. The UVC-CNT light sources exhibit the highest light extraction efficiency when the Al reflector layer has an optimized thickness of 100 nm. For comparison, the cathodoluminescence (CL) spectra were recorded for UVC\u2013CNT light sources with and without the optimized Al reflector. The measured light output power and the estimated power efficiency of the UVC\u2013CNT light-source-tube with Al reflector were enhanced by about 27 times over the reference. This enhancement is mainly attributed to the outstanding reflection effect of the Al reflector.<\/jats:p>","DOI":"10.3390\/molecules26134025","type":"journal-article","created":{"date-parts":[[2021,7,1]],"date-time":"2021-07-01T02:44:39Z","timestamp":1625107479000},"page":"4025","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Optimized Aluminum Reflector for Enhancement of UVC Cathodoluminescence Based-AlGaN Materials with Carbon Nanotube Field Emitters"],"prefix":"10.3390","volume":"26","author":[{"given":"Manoj Kumar Chandra","family":"Mohan","sequence":"first","affiliation":[{"name":"Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sang Kyun","family":"Shim","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"June Key","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, Korea"},{"name":"SBK Materials Co., Gwangju 61186, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nakwon","family":"Jang","sequence":"additional","affiliation":[{"name":"Division of Electrical & Electronic Engineering, Korea Maritime University, Busan 49112, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naesung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1298-7784","authenticated-orcid":false,"given":"Wael Z.","family":"Tawfik","sequence":"additional","affiliation":[{"name":"Department of Physics, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"073103","DOI":"10.1063\/1.3103321","article-title":"Efficiency of light emission in high aluminum content AlGaN quantum wells","volume":"105","author":"Shatalov","year":"2009","journal-title":"J. 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C"}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/26\/13\/4025\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:24:23Z","timestamp":1760163863000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/26\/13\/4025"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,30]]},"references-count":30,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2021,7]]}},"alternative-id":["molecules26134025"],"URL":"https:\/\/doi.org\/10.3390\/molecules26134025","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,30]]}}}