The characteristics of graphene obtained from rice husk and graphite

In this paper a method for obtaining graphene oxide from rice husk were developed using an approach based on a four-stage strategy: Preliminary carbonization, desilication, activation with KOH, and exfoliation and its comparison with the method of graphite oxidation. The samples were analyzed by SEM, TEM, Raman, TGA, FTIR and elemental analysis. The elemental analysis show that the proposed approach allows to produce graphene materials with the content of carbon of about 70% and rich in inorganic matter (0-20 wt.%) (K, Fe, Si). To remove inorganic contents, purification and functionalization step were applied. The Raman spectra of the samples indicate the presence of a mixture of graphene layers and amorphous carbon. The thermogravimetric profile of samples is characterized by a slowly weight decrease up to a final residue of ~10 wt.%. FTIR spectra are characterized by a typical broad shape of large condensed aromatic carbon bonds. The work novelty can be reported as one method, one method of chemical synthesis. The use of a natural precursor - rice husk makes this method very economical for largescale production.