Polyaniline as a precursor of multi-layer graphene: Microscopic and microspectroscopic study

Abstract

Aluminosilicate-based nanocomposites containing multi-layer graphene were prepared from polyaniline/montmorillonite intercalate in two different forms: tablets and thin layers. Starting materials, polyaniline/montmorillonite powder and polyaniline/montmorillonite layers deposited on quartz glass, were prepared by in situ polymerization of aniline in presence of montmorillonite particles. Powder was compacted into tablets using pressure 400 MPa. Samples were calcined at 1300 degrees C in argon atmosphere and multi-layer graphene was formed from polyaniline in both cases as confirmed by Raman microspectroscopy. Changes in morphology and surface conductivity of uncalcined and calcined samples were observed using atomic force microscopy and conductive atomic force microscopy. Also the differences between surface and internal volume of tablets were studied. Conductive atomic force microscopy revealed that the most conductive areas can be found solely on the edges of aluminosilicate particles formed from montmorillonite during calcination process. Detailed observation of multi-layer graphene in these areas was performed using transmission electron microscopy.