Fig. 2
From: Direct imaging of light-element impurities in graphene reveals triple-coordinated oxygen
STEM images of different configurations of oxygen and nitrogen atoms in graphene. a Oxygen pair. b Graphitic substitution by oxygen. c Oxygen atoms within vacancies. d Nitrogen-doped graphene configurations.e Distribution of the different configurations in GO (red) and N-doped graphene (blue). f Distribution of double-coordinated and triple-coordinated heteroatoms in GO (red) and N-doped graphene (blue). N shows the total number of heteroatoms of each sample (note that some configurations contain multiple heteroatoms). Scale bars are 0.5 nm
