Impact of the in situ rise in hydrogen partial pressure on graphene shape evolution during CVD growth of graphene† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7ra13169k

Impact of the in-situ rise of hydrogen partial pressure on graphene shape evolution during CVD growth of graphene Zewdu M.Gebeyehu, Aloïs Arrighi, Marius V. Costache, Clivia M. Sotomayor-Torres, Maria J. Esplandiu, Sergio O. Valenzuela Methods Copper foil preparation A 25 μm thick copper foil (99.8%, Alfa Aesar, stock #13382) was cleaned in acetone and isopropyl alcohol (IPA) for 10 min each to remove organic contaminants. In order to remove surface oxides and other inorganic contaminants, the copper foil was chemically etched using acetic acid/water (1/3) and then thoroughly rinsed with DI water followed by blow-drying with nitrogen gas. For the inspection of the hydrogen etching impact on the catalyst geometrical arrangement (confinment), the copper foil was subjected to a different confinement. In brief, the copper foil was bent into two parts to make half of the copper foil part vertical (non-confined) and half part horizontal (confined) by sandwiching (Fig. 5 )it between the sample holder and the quartz glass slide.