Eurasian Chemico-Technological Journal 21 (2019) 149-156 *Corresponding author. E-mail: makpal_90.90@mail.ru © 2019 Eurasian Chemico-Technological Journal. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.18321/ectj825 The Characteristics of Graphene Obtained from Rice Husk and Graphite M.A. Seitzhanova 1,2, *, Z.A. Mansurov 2 , M. Yeleuov 2 , V. Roviello 3 , R. Di Capua 4 1 Al-Farabi Kazakh National University, 050038 al-Farabi ave. 71, Almaty, Kazakhstan 2 Institute of Combustion Problems, 050012, Bogenbay batyr str. 172, Almaty, Kazakhstan 3 Advanced Metrologic Service Center (CESMA), University of Naples Federico II, Naples, Italy 4 Department of Physics, University of Naples Federico II, and CNR-SPIN, Naples, Italy Abstract 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, purifcation 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 profle of samples is characterized by a slowly weight decrease up to a fnal 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 large- scale production. Article info Received: 20 December 2018 Received in revised form: 6 February 2019 Accepted: 27 March 2019 Keywords Graphene Graphite Rice husk Carbonization Chemical activation 1. Introduction Recently, graphene and graphene oxides (GO) have found independent use as materials for nano- electronics, component of polymer and inorganic composite materials, solar batteries, supercapaci- tors, membranes, adsorbents, quantum dots, fuo- rescent material for biology and medicine [1–4]. Graphene is a semimetal with overlap of the valence and the conduction bands (material with zero band- gap) [5]. Unlike the ideal graphene sheet, graphene oxides consist of a 2D mesh of bound carbon at- oms in the sp 2 and sp 3 hybridization states. Most sp3 hybridized carbon atoms in graphene oxides are covalently bounded with oxygen in the form of epoxy, hydroxyl, and carboxyl groups [6–12]. Synthesis of graphene (single layer of graph- ite) has been reported as early as in 1975 by B. Lang [13]. After several attempts by various sci- entists, eventually Novoselov et al. received credit for the discovery of graphene in 2004 [14]. They presented a reproducible method for the synthesis of graphene by mechanical exfoliation, but this method is not suitable for large-scale production. There are other well-known methods also available for the synthesis of graphene, which are associat- ed with a number of mechanical operations: mix- ing, spraying, impregnation [15]. In this regard, compared with the powder state of the substance, it is more convenient to use colloidal dispersions. Among the methods for obtaining colloidal disper- sions of graphene oxide, chemical methods pre- vail. Moreover, the main advantages of chemical methods are the possibility of large-scale produc- tion of the product and the relative simplicity of its functionalization due to the presence of active oxygen-containing groups [16]. Currently, many researchers are trying to develop green synthesis processes for graphene production [17–18, 3]. The purpose of green synthesis methods is to use a nat- ural precursor and not to use toxic chemicals.