{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T07:27:14Z","timestamp":1781335634307,"version":"3.54.1"},"reference-count":43,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2024,8,24]],"date-time":"2024-08-24T00:00:00Z","timestamp":1724457600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bulgarian National Science Fund","award":["KP-06-N69\/8"],"award-info":[{"award-number":["KP-06-N69\/8"]}]},{"name":"Bulgarian National Science Fund","award":["KP-06-N57\/5"],"award-info":[{"award-number":["KP-06-N57\/5"]}]},{"name":"Bulgarian National Science Fund","award":["BG05M2OP001-1.001-0008"],"award-info":[{"award-number":["BG05M2OP001-1.001-0008"]}]},{"name":"the European Regional Development Fund","award":["KP-06-N69\/8"],"award-info":[{"award-number":["KP-06-N69\/8"]}]},{"name":"the European Regional Development Fund","award":["KP-06-N57\/5"],"award-info":[{"award-number":["KP-06-N57\/5"]}]},{"name":"the European Regional Development Fund","award":["BG05M2OP001-1.001-0008"],"award-info":[{"award-number":["BG05M2OP001-1.001-0008"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Semiconductor oxides are frequently used as active photocatalysts for the degradation of organic agents in water polluted by domestic industry. In this study, sol-gel ZnO thin films with a grain size in the range of 7.5\u201315.7 nm were prepared by applying a novel two-step drying procedure involving hot air treatment at 90\u201395 \u00b0C followed by conventional furnace drying at 140 \u00b0C. For comparison, layers were made by standard furnace drying. The effect of hot air treatment on the film surface morphology, transparency, and photocatalytic behavior during the degradation of Malachite Green azo dye in water under ultraviolet or visible light illumination is explored. The films treated with hot air demonstrate significantly better photocatalytic activity under ultraviolet irradiation than the furnace-dried films, which is comparable with the activity of unmodified ZnO nanocrystal powders. The achieved percentage of degradation is 78\u201382% under ultraviolet illumination and 85\u201390% under visible light illumination. Multiple usages of the hot air-treated films (up to six photocatalytic cycles) are demonstrated, indicating improved photo-corrosion resistance. The observed high photocatalytic activity and good photo-corrosion stability are related to the hot air treatment, which causes a reduction of oxygen vacancies and other defects and the formation of interstitial oxygen and\/or zinc vacancies in the films.<\/jats:p>","DOI":"10.3390\/molecules29174005","type":"journal-article","created":{"date-parts":[[2024,8,26]],"date-time":"2024-08-26T03:14:31Z","timestamp":1724642071000},"page":"4005","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Enhanced Photocatalytic Performance under Ultraviolet and Visible Light Illumination of ZnO Thin Films Prepared by Modified Sol-Gel Method"],"prefix":"10.3390","volume":"29","author":[{"given":"Radka","family":"Gegova-Dzhurkova","sequence":"first","affiliation":[{"name":"G. Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diana","family":"Nesheva","sequence":"additional","affiliation":[{"name":"G. Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irina","family":"Stambolova","sequence":"additional","affiliation":[{"name":"Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katerina","family":"Zaharieva","sequence":"additional","affiliation":[{"name":"Institute of Mineralogy and Crystallography \u201cAcad. Ivan Kostov\u201d, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valeri","family":"Dzhurkov","sequence":"additional","affiliation":[{"name":"G. Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilko","family":"Miloushev","sequence":"additional","affiliation":[{"name":"G. Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2300001","DOI":"10.1002\/gch2.202300001","article-title":"A state-of-art review of the metal oxide-based nanomaterials effect on photocatalytic degradation of malachite green dyes and a bibliometric analysis","volume":"7","author":"Umar","year":"2023","journal-title":"Glob. Chall."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Podasca, V.-E., and Damaceanu, M.-D. (2020). 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