Fig. 2From: Interfactant action of an amphiphilic polymer upon directing graphene oxide layer formation on sapphire substratesXPS results obtained in the binding energy region between 0 and 700 eV for A a pristine sapphire surface, B a G50/sapphire interfactant film (sample G50-17h), C a GO/G50/sapphire film, and D a dried deposit of water-rinsed GO dispersionBack to article page