{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T03:57:25Z","timestamp":1793419045118,"version":"4.5.0"},"reference-count":51,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2025,2,28]],"date-time":"2025-02-28T00:00:00Z","timestamp":1740700800000},"content-version":"vor","delay-in-days":1,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006151","name":"Basic Energy Sciences","doi-asserted-by":"publisher","award":["DE-SC0022278"],"award-info":[{"award-number":["DE-SC0022278"]}],"id":[{"id":"10.13039\/100006151","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,2,27]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>Carbon dioxide removal (CDR) involves reducing carbon dioxide (CO\u2082) concentrations. Developing new technologies and enhancing existing ones for extracting and converting CO\u2082 are ongoing areas of research. In all these technologies, the movement of CO2 molecules through an interface is a common process. At liquid surfaces, the nanometer-thick interfacial region is expected to play a fundamental role in enhancing or hindering the process. The interface can have significantly different conditions, such as pH, ion concentration, and ion speciation, compared with the bulk. Despite this, our knowledge of the molecular-scale details of CO2 capture and conversion at liquid interfaces is limited. Here, we report direct observation of CO2 surface adsorption and conversion to bicarbonate at the air\/aqueous interface of potassium orthovanadate solutions using vibrational sum frequency generation spectroscopy. We show that orthovanadate ions enhance the hydrated CO2 population at the interface, indicated by a strong peak at 2,336\u2005cm\u22121. DFT calculations suggest that CO2 molecules are bent with respect to their original linear structure, demonstrating the initiation of CO2 to HCO3\u2212 conversion. With increasing orthovanadate concentration and\/or time of exposure, the CO2 peak disappears, and (bi)carbonate peaks appear. The characterization of the bulk solutions as well as the precipitated products suggests that the observed interfacial species are transient, different from the final products. This study provides a better understanding of CO2 transport into aqueous media, not only for CDR technologies but also for environmental and atmospheric chemistry in general.<\/jats:p>","DOI":"10.1093\/pnasnexus\/pgaf064","type":"journal-article","created":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T21:38:48Z","timestamp":1741124328000},"source":"Crossref","is-referenced-by-count":11,"title":["Direct observation of carbon dioxide adsorption and binding at the air\/aqueous interface"],"prefix":"10.1093","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5320-1207","authenticated-orcid":false,"given":"Mokhtar","family":"Rashwan","sequence":"first","affiliation":[{"name":"Chemical Sciences and Engineering Division, Argonne National Laboratory , Lemont, IL 60439 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