Photocatalytic Pavements as an Active CO2 Mitigation Tool: Quantifying the CO2 Removal Potential of TiO2-based Concrete Surface Treatments

Photocatalytic Pavements as an Active CO2 Mitigation Tool: Quantifying the CO2 Removal Potential of TiO2-based Concrete Surface Treatments | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Photocatalytic Pavements as an Active CO 2 Mitigation Tool: Quantifying the CO 2 Removal Potential of TiO 2 -based Concrete Surface Treatments Marina Lopez-Arias, Rui Bai, Mirian Velay-Lizancos This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9452430/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The growing pollution from transportation into the environment has created an urgent need for active mitigation tools. Photocatalytic surface treatments for concrete pavements, such as TiO 2 -based surface treatments, offer a promising solution by continuously reducing pollutants using solar energy. While previous research has shown that TiO 2 surface treatments on concrete can reduce CO 2 concentrations through photoreduction, quantifying the CO 2 reduction remains necessary to understand their full potential under realistic conditions. This study presents a novel estimation model trained on experimental data from concrete slabs exposed to different light intensities (0, 23, and 100 W/m 2 ) and CO 2 concentrations (6%, 12%, and 100%) to estimate CO 2 reduction (CDR). Results showed that both higher CO 2 concentrations and higher light irradiance levels led to greater CDR, with maximum reductions of 0.2 g/m 2 per hour under 6% CO 2, 1.6 g/m 2 per hour under 12% CO 2 , and 79.2 g/m 2 per hour under 100% CO 2 , at 100 W/m 2 irradiance. Two models were developed: a linear model, assuming CDR increases linearly with light irradiance, and a conservative model, with CDR plateauing at 100 W/m 2 . Using real sunlight irradiance and traffic data, the model estimates an annual reduction of 5.8–6.8 kg/m 2 with the conservative model, while up to 25.8 kg/m 2 with the linear model. Scaling it to 100 km of road, the TiO 2 surface treatment could remove up to 4.1 M kg of CO 2 annually in cities like Phoenix and 3.7 M kg in Seattle, demonstrating the potential of this technology for large-scale carbon removal. Civil Engineering Photocatalysis TiO2 CO2 photoreduction Concrete Pavements surface treatment Full Text Additional Declarations The authors declare no competing interests. Supplementary Files Supplementarymaterial.pdf Supplementary material Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9452430","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":625193528,"identity":"0385e043-c4c7-4618-a550-96a419632697","order_by":0,"name":"Marina Lopez-Arias","email":"","orcid":"https://orcid.org/0000-0002-2906-0280","institution":"University of California, Merced","correspondingAuthor":false,"prefix":"","firstName":"Marina","middleName":"","lastName":"Lopez-Arias","suffix":""},{"id":625193529,"identity":"e22f8f4c-8ace-489e-b3b2-2ecf499a3c7b","order_by":1,"name":"Rui Bai","email":"","orcid":"","institution":"Purdue 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transportation into the environment has created an urgent need for active mitigation tools. Photocatalytic surface treatments for concrete pavements, such as TiO\u003csub\u003e2\u003c/sub\u003e-based surface treatments, offer a promising solution by continuously reducing pollutants using solar energy. While previous research has shown that TiO\u003csub\u003e2\u003c/sub\u003e surface treatments on concrete can reduce CO\u003csub\u003e2\u003c/sub\u003e concentrations through photoreduction, quantifying the CO\u003csub\u003e2\u003c/sub\u003e reduction remains necessary to understand their full potential under realistic conditions. This study presents a novel estimation model trained on experimental data from concrete slabs exposed to different light intensities (0, 23, and 100 W/m\u003csup\u003e2\u003c/sup\u003e) and CO\u003csub\u003e2\u003c/sub\u003e concentrations (6%, 12%, and 100%) to estimate CO\u003csub\u003e2\u003c/sub\u003e reduction (CDR). 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