Fig. 2: Correlation maps and statistical distributions of G and 2D Raman frequencies (wG and w2D) for graphene on different solid and liquid supports.
a Graphene on copper, graphene at water/air interface, graphene at water/cyclohexane interface, graphene at water/1-octanol interface and free-standing graphene on a quantifoil grid. Black and red dash lines represent the strain and doping axes respectively. Laser excitation wavelength is 457 nm. b Graphene on Si/SiO2 wafer, graphene at water/air interface, graphene at water/cyclohexane interface, graphene at water/1-octanol interface and free-standing graphene on a quantifoil grid. Black and red dash lines represent the strain and doping axes (lines of zero doping and zero strain) respectively. Numbers represent values of strain and doping. Laser excitation wavelength is 532 nm.
