{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:29:27Z","timestamp":1760059767261,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,7,13]],"date-time":"2025-07-13T00:00:00Z","timestamp":1752364800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002322","name":"Brazilian agencies Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior","doi-asserted-by":"publisher","award":["001","UIDB\/00313\/2025","UIDP\/00313\/2025"],"award-info":[{"award-number":["001","UIDB\/00313\/2025","UIDP\/00313\/2025"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)","award":["001","UIDB\/00313\/2025","UIDP\/00313\/2025"],"award-info":[{"award-number":["001","UIDB\/00313\/2025","UIDP\/00313\/2025"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT\u2014Portuguese Agency for Scientific Research)","award":["001","UIDB\/00313\/2025","UIDP\/00313\/2025"],"award-info":[{"award-number":["001","UIDB\/00313\/2025","UIDP\/00313\/2025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Reactions"],"abstract":"<jats:p>Dye-sensitized solar cells (DSSCs) have emerged as a promising technology for converting sunlight into electricity at a low cost; however, it is still necessary to find a photostable, low-cost, and efficient photosensitizer. In this sense, the natural product bixin (Dye 1) has previously been reported as a potential photosensitizer. Thus, the present work reports the full synthesis of diester and diacid hybrids (Dyes 2 and 3, respectively, with corresponding yields of 93% and 52%) using the natural product bixin as a starting material and 1,3,4-oxadiazole ring as a connected point. The hydrolysis step of Dye 2 aims to obtain Dye 3 with a structural capacity to anchor the titanium dioxide (TiO2) nanofilms via the carboxylic acid group. Both compounds (Dyes 1 and 3) can be adsorbed via pseudo-first order on the surface of TiO2 nanofilms, reaching saturation after 10 and 6 min of exposure in an organic solution (1 \u00d7 10\u22125 M), respectively, with adsorption kinetics of the semisynthetic compound almost twofold higher than the natural product. Contrary to expectations, Dye 3 had spectral behavior similar to Dye 1, but with better frontier molecular orbital (FMO) parameters, indicating that Dye 3 will probably behave very similarly or have slightly better photovoltaic performance than Dye 1 in future DSSC measurements.<\/jats:p>","DOI":"10.3390\/reactions6030039","type":"journal-article","created":{"date-parts":[[2025,7,14]],"date-time":"2025-07-14T09:56:54Z","timestamp":1752487014000},"page":"39","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Studies on a New 1,3,4-Oxadiazole Bixin Dimer for Potential Application in Dye-Sensitized Solar Cells"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7188-833X","authenticated-orcid":false,"given":"Afonso Santine M. M.","family":"Velez","sequence":"first","affiliation":[{"name":"Department of Organic Chemistry, Institute of Chemistry, Federal Rural University of Rio de Janeiro (UFRRJ), Serop\u00e9dica 23890-000, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5897-6020","authenticated-orcid":false,"given":"Daniela","family":"Pinheiro","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Coimbra Chemistry Centre\u2014Institute of Molecular Sciences (CQC-IMS), University of Coimbra, Rua Larga, 3004-545 Coimbra, Portugal"},{"name":"Center of Potential and Innovation of Natural Resources (CPIRN-IPG), Polytechnic of Guarda, 6300-559 Guarda, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7004-0110","authenticated-orcid":false,"given":"Carlos","family":"Serpa","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Coimbra Chemistry Centre\u2014Institute of Molecular Sciences (CQC-IMS), University of Coimbra, Rua Larga, 3004-545 Coimbra, Portugal"}]},{"given":"Rosane Nora","family":"Castro","sequence":"additional","affiliation":[{"name":"Department of Organic Chemistry, Institute of Chemistry, Federal Rural University of Rio de Janeiro (UFRRJ), Serop\u00e9dica 23890-000, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0563-3483","authenticated-orcid":false,"given":"Marco Edilson Freire de","family":"Lima","sequence":"additional","affiliation":[{"name":"Department of Organic Chemistry, Institute of Chemistry, Federal Rural University of Rio de Janeiro (UFRRJ), Serop\u00e9dica 23890-000, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6211-7659","authenticated-orcid":false,"given":"Ot\u00e1vio Augusto","family":"Chaves","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Coimbra Chemistry Centre\u2014Institute of Molecular Sciences (CQC-IMS), University of Coimbra, Rua Larga, 3004-545 Coimbra, Portugal"},{"name":"Laboratory of Immunopharmacology, Centro de Pesquisa, Inova\u00e7\u00e3o e Vigil\u00e2ncia em COVID-19 e Emerg\u00eancias Sanit\u00e1rias (CPIV), Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 21040-361, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"814","DOI":"10.1142\/S1088424613500454","article-title":"Ti (IV) phthalocyanines for dye sensitized solar cells","volume":"17","author":"Torres","year":"2013","journal-title":"J. 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