{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T05:35:44Z","timestamp":1763703344614,"version":"3.45.0"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,19]],"date-time":"2025-11-19T00:00:00Z","timestamp":1763510400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology","award":["PRT\/BD\/154269\/2022"],"award-info":[{"award-number":["PRT\/BD\/154269\/2022"]}]},{"name":"POR Norte-Portugal 2020 and State Budget, under MIT Portugal Program","award":["NanoAirPTDC\/FISMAC\/6606\/2020"],"award-info":[{"award-number":["NanoAirPTDC\/FISMAC\/6606\/2020"]}]},{"name":"UIDB\/04650 Centre of Physics of Minho and Porto Universities","award":["UIDB\/04029\/2020"],"award-info":[{"award-number":["UIDB\/04029\/2020"]}]},{"name":"R&D Unit Institute for Sustainability and Innovation in Structural Engineering","award":["UIDB\/04029\/2020"],"award-info":[{"award-number":["UIDB\/04029\/2020"]}]},{"name":"Associate Laboratory Advanced Production and Intelligent Systems ARISE","award":["LA\/P\/0112\/2020"],"award-info":[{"award-number":["LA\/P\/0112\/2020"]}]},{"name":"Foundation for Science and Technology","award":["2022.00763.CEECIND"],"award-info":[{"award-number":["2022.00763.CEECIND"]}]},{"name":"CERIS research unit","award":["UIDB\/6438\/2025"],"award-info":[{"award-number":["UIDB\/6438\/2025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Coatings"],"abstract":"<jats:p>Throughout the lifetime, road markings (RMs) accumulate dirt, oils, and greases, which reduce visibility, shorten service life, and compromise road safety. If RMs could degrade these pollutants, their service life would increase. When exposed to UV light and humidity, semiconductors, such as titanium dioxide (TiO2), can interact with contaminants and promote their chemical degradation. Semiconductors are commonly used on different types of substrates to achieve self-cleaning ability. In this study, 0.25\u20133 wt% TiO2 was incorporated into a commercial RM paint for this purpose. After functionalization, the RM paint samples were contaminated with Methylene Blue and Rhodamine B. After pollution, the specimens were irradiated with a light source that simulates sunlight. To assess the self-cleaning capacity of the paints, visual analysis, color variation and discoloration by using CIELAB color coordinates, diffuse reflectance, and digital image processing techniques were applied. In both techniques, the samples with 2% and 3% of TiO2 showed a greater capacity to degrade pollutants. Further, the chemical and morphological characteristics of the reference paint and the samples that showed the best self-cleaning results were analyzed by using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), and X-ray Diffraction (XRD). They identified the polymer, filler, and pigment in the commercial paint and confirmed the TiO2 increase after functionalization. This study demonstrated the innovative potential of incorporating semiconductors to achieve a new capability (self-cleaning) for RM paints. This breakthrough not only has the potential to extend the RM service life, but also to improve road safety through greater visibility.<\/jats:p>","DOI":"10.3390\/coatings15111349","type":"journal-article","created":{"date-parts":[[2025,11,19]],"date-time":"2025-11-19T12:55:31Z","timestamp":1763556931000},"page":"1349","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Self-Cleaning Road Marking Paints for Improved Road Safety: Multi-Scale Characterization and Performance Evaluation Using Rhodamine B and Methylene Blue as Model Pollutants"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5702-006X","authenticated-orcid":false,"suffix":"Jr.","given":"Orlando","family":"Lima","sequence":"first","affiliation":[{"name":"Advanced Production and Intelligent Systems Associated Laboratory (ARISE), Department of Civil Engineering, Institute for Sustainability and Innovation in Structural Engineering (ISISE), University of Minho, 4800-058 Guimar\u00e3es, Portugal"},{"name":"Physics Centre of Minho and Porto Universities (CF-UM-UP), Azur\u00e9m Campus, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4199-5994","authenticated-orcid":false,"given":"Iran Rocha","family":"Segundo","sequence":"additional","affiliation":[{"name":"CERIS, Instituto Superior T\u00e9cnico, University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5260-1914","authenticated-orcid":false,"given":"Laura","family":"Mazzoni","sequence":"additional","affiliation":[{"name":"Department of Transportation Engineering, Polytechnic School of the University of S\u00e3o Paulo, S\u00e3o Paulo 05508-070, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5132-7407","authenticated-orcid":false,"given":"Elisabete","family":"Freitas","sequence":"additional","affiliation":[{"name":"Advanced Production and Intelligent Systems Associated Laboratory (ARISE), Department of Civil Engineering, Institute for Sustainability and Innovation in Structural Engineering (ISISE), University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9778-5390","authenticated-orcid":false,"given":"Joaquim","family":"Carneiro","sequence":"additional","affiliation":[{"name":"Physics Centre of Minho and Porto Universities (CF-UM-UP), Azur\u00e9m Campus, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"103123","DOI":"10.1016\/j.trd.2021.103123","article-title":"Microplastics and Road Markings: The Role of Glass Beads and Loss Estimation","volume":"102","author":"Burghardt","year":"2022","journal-title":"Transp. 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