Graphene as a Metal-Free Catalyst—Recent Case Studies

One can encounter some skepticism about clean, non-functionalized, defect-free graphene being a catalyst for gas-surface reactions at ultra-high vacuum (UHV). We will describe a few successful literature examples, focusing on our own recent work, to illustrate that graphene indeed can act as a catalyst. Experimental and theoretical results will be described. Our own work concerns the decomposition of small sulfur compounds (SO2, H2S, thiophene) on epitaxial graphene characterized in UHV by surface science experimental and theoretical techniques. Desulfurization catalysis has some overlap with energy-related applications. Other recent works from other groups concern the surface chemistry of organic compounds, as well as the dissociation of hydrogen on corrugated graphene. This book chapter does not provide a comprehensive review, however. A few liquid phase studies, work on powder samples, electrochemistry, and photoelectrochemistry works are mentioned but not discussed in any detail. The case studies focus on defect-free and clean (not functionalized), epitaxial graphene as the catalyst studied at UHV.