64261 2025 eng lecture 0 -- -- -- Reliable quantification of the chemical composition of graphene-related 2D materials (GR2M) as powders and liquid suspensions is a challenging task. Analytical methods such as XPS, ICP-MS, TGA and FTIR are recommended in projects at standardization bodies. The parameters to be measured are also defined, e.g. the oxygen-to-carbon (O/C) concentration ratio, the trace metal impurities, or the functional groups present. In this contribution, for the first time, the capability of SEM/EDS to reliably quantify the O/C ratio in a well-characterized graphene oxide (GO) material is evaluated. The robustness of the SEM/EDS results under various measurement conditions is tested by comparison to the established XPS analysis. A crucial step is the sample preparation from liquid suspension with GO flakes onto a substrate for analysis with both EDS and XPS. It is demonstrated that if a closed and enough thick drop-cast spot is deposited on a substrate, both surface-sensitive XPS analysis and bulk-characterizing EDS result in very similar elemental composition of oxygen and carbon. Hence, the theoretical, expected O/C atomic ratio values for pure GO of ~0.5 are achieved with both methods. Further, the effect of untight deposited material causing co-analysis of the silicon substrate, is evaluated for both methods, XPS and EDS. Note that all the EDS results in this study have been quantified standardless. The standard measurement procedure including the GO material considered here as a candidate reference material will make a significant contribution to analyse reliably the chemical composition of GR2M with SEM/EDS as one of the most widely used methods in analytical laboratories. Graphene Week 2025 Vicenza, Italy 22.09.2025 26.09.2024 0 publish false true Vasile-Dan Hodoroaba eng uncontrolled EDX eng uncontrolled Graphene-related 2D materials eng uncontrolled O/C ratio eng uncontrolled Standardisation eng uncontrolled Samle preparation eng uncontrolled XPS Ingenieurwissenschaften und zugeordnete Tätigkeiten 6 Materialchemie 6.1 Oberflächen- und Dünnschichtanalyse Material Datei im Netzwerk der BAM verfügbar ("Closed Access") Präsentation Advanced Materials