{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T23:49:29Z","timestamp":1762300169816,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2022,9,20]],"date-time":"2022-09-20T00:00:00Z","timestamp":1663632000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"national funds from FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"],"award-info":[{"award-number":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"]}]},{"name":"European Community\u2019s H2020 program","award":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"],"award-info":[{"award-number":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"]}]},{"DOI":"10.13039\/501100001871","name":"Ph.D scholarship","doi-asserted-by":"publisher","award":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"],"award-info":[{"award-number":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Ph.D scholarship","doi-asserted-by":"publisher","award":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"],"award-info":[{"award-number":["952169","DFA\/BD\/7882\/2020","SFRH\/BD\/148078\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>The inexorable increase of energy demand and the efficiency bottleneck of monocrystalline silicon solar cell technology is promoting the research and development of alternative photovoltaic materials. Copper-arsenic-sulfide (CAS) compounds are still rather unexplored in the literature, yet they have been regarded as promising candidates for use as p-type absorber in solar cells, owing to their broad raw material availability, suitable bandgap and high absorption coefficient. Here, a comprehensive study is presented on the structural and optoelectronic properties of CAS thin-films deposited via radio-frequency magnetron co-sputtering, using a commercial Cu target together with a Cu-As-S target with material obtained from local resources, specifically from mines in the Portuguese region of the Iberian Pyrite Belt. Raman and X-ray diffraction analysis confirm that the use of two targets results in films with pronounced stoichiometry gradients, suggesting a transition from amorphous CAS compounds to crystalline djurleite (Cu31S16), with the increasing proximity to the Cu target. Resistivity values from 4.7 m\u2126\u00b7cm to 17.4 \u2126\u00b7cm are obtained, being the lowest resistive films, those with pronounced sub-bandgap free-carrier absorption. The bandgap values range from 2.20 to 2.65 eV, indicating promising application as wide-bandgap semiconductors in third-generation (e.g., multi-junction) photovoltaic devices.<\/jats:p>","DOI":"10.3390\/nano12193268","type":"journal-article","created":{"date-parts":[[2022,9,20]],"date-time":"2022-09-20T22:36:44Z","timestamp":1663713404000},"page":"3268","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Copper-Arsenic-Sulfide Thin-Films from Local Raw Materials Deposited via RF Co-Sputtering for Photovoltaics"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4868-1813","authenticated-orcid":false,"given":"Pedro","family":"Centeno","sequence":"first","affiliation":[{"name":"CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP\/UNINOVA, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7533-9469","authenticated-orcid":false,"given":"Miguel","family":"Alexandre","sequence":"additional","affiliation":[{"name":"CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP\/UNINOVA, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1251-053X","authenticated-orcid":false,"given":"Filipe","family":"Neves","sequence":"additional","affiliation":[{"name":"LNEG, Laborat\u00f3rio Nacional de Energia e Geologia, Estrada do Pa\u00e7o do Lumiar 22, 1649-038 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4202-7047","authenticated-orcid":false,"given":"Elvira","family":"Fortunato","sequence":"additional","affiliation":[{"name":"CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP\/UNINOVA, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1997-7669","authenticated-orcid":false,"given":"Rodrigo","family":"Martins","sequence":"additional","affiliation":[{"name":"CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP\/UNINOVA, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7350-649X","authenticated-orcid":false,"given":"Hugo","family":"\u00c1guas","sequence":"additional","affiliation":[{"name":"CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP\/UNINOVA, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7374-0726","authenticated-orcid":false,"given":"Manuel J.","family":"Mendes","sequence":"additional","affiliation":[{"name":"CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP\/UNINOVA, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1002\/pip.3506","article-title":"Solar Cell Efficiency Tables (Version 59)","volume":"30","author":"Green","year":"2022","journal-title":"Prog. 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