Fig. 4
From: Surfactant mediated liquid phase exfoliation of graphene
Diazaperopyrenium for effective graphene exfoliation. a-b Structural formulas of diazaperopyrenium dication (MP2+) a and diazapyrenium dication (DAP2+) (b). c-e Photographs of graphite/H2O(c), MP.2Cl/ H2O d and graphite/ MP.2Cl /H2O under ambient light and under UV light (insets). (f) TEM images of MP •2Cl/Graphene composite material. g SAED pattern of MP •2Cl/ Graphene. h AFM height image of MP •2Cl/Graphene. (i) Height profile of AFM image corresponding to the line shown in Fig. 4(h). j Probability of occurrence of graphene layers with various thickness measured by AFM height image. a-j reproduced from ref. 45 with permission, © Wiley-VCH)