biostudies-literatureKust USvenska Forskningsrådet FormasVetenskapsrådetVetenskapsrådet (Swedish Research Council)Ministero dell'Istruzione, dell'Università e della RicercaVINNOVA (Swedish Governmental Agency for Innovation Systems)Ministero dell'Istruzione, dell'Università e della Ricerca (Ministry of Education, University and Research)VINNOVASvenska Forskningsrådet Formas (Swedish Research Council Formas)7755https://www.ebi.ac.uk/biostudies/studies/S-EPMC12368142biostudies-literatureUnknown16(1)Separating how surface and subsurface species affect catalytic function is a challenging task in heterogeneous catalysis, particularly when deposition and segregation take place at reaction conditions. Here, we report on an operando approach to establish surface/subsurface/function correlations. Using temperature modulations we oscillate carbon deposition and segregation over a Pd catalyst. Catalytic composition and function are monitored during methane oxidation showing that the surface coverage of carbon drives partial oxidation to CO, while subsurface carbon controls the overall methane turnover. Also, we show that a carbon traffic jam in the subsurface leads to a shifting selectivity from H2 to H2O formation, highlighting the importance of the catalyst subsurface for the catalytic reacNature communicationsCarbon subsurface traffic jam as driver for methane oxidation activity and selectivity on palladium surfaces.PMC123681422019-024962018-04969PNRR DM 3512017- 04840, 2018-07152, 2022-04363Scardamaglia MKust UNamar AKnudsen JPrumbs JJones RShavorskiy AfalseCarbon subsurface traffic jam as driver for methane oxidation activity and selectivity on palladium surfaces.Separating how surface and subsurface species affect catalytic function is a challenging task in heterogeneous catalysis, particularly when deposition and segregation take place at reaction conditions. Here, we report on an operando approach to establish surface/subsurface/function correlations. Using temperature modulations we oscillate carbon deposition and segregation over a Pd catalyst. Catalytic composition and function are monitored during methane oxidation showing that the surface coverage of carbon drives partial oxidation to CO, while subsurface carbon controls the overall methane turnover. Also, we show that a carbon traffic jam in the subsurface leads to a shifting selectivity from H2 to H2O formation, highlighting the importance of the catalyst subsurface for the catalytic reac2025-01-01T00:00:00Z2025 Aug2026-05-05T19:02:18.168Z2026-04-07T21:50:55.933ZS-EPMC123681424083583610.1038/s41467-025-63088-9