A so-called quasi in-situ XPS approach was used to explore the surface composition and speciation of the bimetallic systems giving the best CO and HCOO -perf ormance. CO2 electrolysis was carried out at various potentials in an O2-f ree glovebox under inert (N2) atmosphere. Then, the measured samples were rapidly transf erred to the XPS analysis chamber under vacuum without any air exposure through a gastight transfer capsule. In this way, we sought to avoid the re-oxidation of the tested catalysts' surfaces, providing chemical and compositional insight more representative of their real surface-active species. The quasi in-situ XPS results are summarized in Immediately noticeable is that while the surf ace of the dif ferent as-prepared bimetallic foams and their single-metal counterparts (Cu, Sn and In) are mostly dominated by oxide species (e.g., CuxOy, SnOx and InxOy) (Figure ), the samples measured after electrocatalysis have distinctly transformed surface speciation.