ИСТИНА

According to XANES (X-Rays Absorption Near Edge Structure) and EXAFS (Extended X-Ray Absorption Fine Structure) data graphene nanoflakes layered structure demonstrate the affinity to the Fe single-atoms that are intercalated during their formation and stabilized between the planes. Even after additional acidic treatment by HNO3, that is required for purification and necessary for the majority of applications, XANES and EXAFS technique show that only structural changes in Fe local environment occur without affecting the oxidation state of the metal. This process began after prolongated treatment by the acid and leads to partial destroy of the fine layered structure. Even being finished, Fe atoms can be detected between the rest of the graphene structure. Present study was funded by Russian Science Foundation, project 18-03-00217. Authors are grateful to Prof. Dr. Kristina Kvashnina and PhD Elena Bazarkina for their assistance in XAS measurements at the ESRF.