Performance of graphene sheets as stationary phase for capillary gas chromatographic separations

• Graphene as a new π–π type of GC stationary phase.
• Specific retention mainly via π–π stacking and H-bonding interactions.
• High resolving ability for aromatics and polar analytes.

This work presents the investigation of graphene as a new type of stationary phase for capillary GC separations. Graphene capillary column (0.25 mm, i.d.) achieved column efficiency of 3100 plates/m determined by n-dodecane at 120 °C. The obtained McReynolds constants suggested the weakly polar nature of graphene sheets as GC stationary phase. As evidenced, graphene stationary phase differs from the conventional phase (5% phenyl polysiloxane) in its resolving ability and retention behaviors, and achieved better separation for the Grob and other mixtures. The advantages of graphene stationary phase may mainly originate from its specific π–π stacking interaction as well as H-bonding interaction. Furthermore, graphene column exhibited good repeatability with relative standard deviation (RSD%) in the range of 0.01–0.07% for run-to-run and 2.5–6.7% for column-to-column, respectively.