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Different samples of graphite oxide (GrO) were prepared by modification of the Improved Hummers Method reported in the literature. Graphite was used as the raw material and KMnO4 and H2SO4 were used as chemical reagents. GrO samples were analyzed by Raman spectroscopy, SEM, TEM, elemental analysis, X-ray diffraction, N2 adsorption–desorption, and thermogravimetric analysis. The results indicate that, after optimizing the synthesis method, the oxidation time was reduced from 12 to 3 h, coagulation step was removed, wash step was halved, use of H3PO4 during the oxidation step was no longer necessary, the production of graphite oxide per batch was increased, and the amount of graphite that could be processed was increased five times. Therefore, synthesis costs were significantly lower than those related to the published Improved Hummers Method. An economic assessment for the industrial scale demonstrated that this process could be viable from the third year after its implementation.

Graphene is considered the world's strongest and thinnest material, in addition to be a very good heat and electricity conductor. Traditional methods to produce graphene include mechanical exfoliation, Chemical Vapor Deposition or thermal expansion but none of them are attractive from the commercial point of view due to its low yield or the poor quality of the retrieved product [1]. Graphite and graphene oxide are the most important graphene allotropes. Graphite oxide is obtained by generation of oxygenated functional groups on the surface and edges of graphite which, after its layer expansion, provides graphene oxide. Nowadays, graphene oxide reduction (via chemical or thermal routes) seems to be the best method to synthesize graphene at industrial scale [2] although, as a consequence of the experimental procedure followed, some defects remain in the final structure of the product. Graphite oxide can be synthesized by either Brodie, Staudenmaier, or Hummers method and its variations, namely Modified Hummers Method or Improved Hummers Method [3]. Among them, Improved Hummers Method is characterized by its both lower toxicity and several advantages in terms of the resulting products. Even so, the oxidation protocol associated to the Improved Hummed Method clearly depends on the abundant use of strong acids (leading to subsequent environmental issues), high treatment times and tedious purification processes, which results in high manufacture costs [4]. These reasons among others make the industrial commercialization of graphite oxide and its derivative products to be limited. In previously papers, optimization of the Improved Hummers Method (as reported in Literature [3]) which use graphite as the raw material and KMnO 4 and H 2 SO 4 as chemical reagents to produce the oxidation of graphite was reported. Chen et al. [5] proposed in 2013 the elimination of NaNO 3 for the reaction and H 3 PO 4 for graphite oxide washing and demonstrated the disposal of waste water. Lavin-Lopez et al. [6] showed that the oxidation time could be

The optimization of graphene growth on copper foils using an atmospheric pressure chemical vapor deposition setup is reported. CH4 and H2 were used as precursor gases and Raman spectroscopy as the main graphene characterization technique. Different growth parameters, including temperature and reaction time, the molar ratio of CH4/H2 in the feed and total flow of gases during the reaction step, were studied in detail. It was shown that graphene growth was not homogeneous in the entire sample, multilayer graphene was present in most of the sample, however as the synthesis parameters were optimized, graphene gained better quality, obtaining bilayer graphene over most of the sheet in the final optimized sample. Homemade software was used to analyze the quality of the synthesised graphene, obtaining a more quality graphene according to the synthesis parameters optimized. An optimal bilayer graphene sample was prepared at the lowest growth time (10 min) and the highest synthesis temperature (1050 °C), using a CH4/H2 flow ratio and a total flow rate ratio of precursors of 7% and 60 Nml (CH4 + H4) per min respectively.

Graphene, a new 2D material, is gaining a lot of attention because of its remarkable mechanical, electrical, chemical, thermal, and optical properties. Graphene synthesis procedures can follow two different strategies named as "bottom up" and "top down". In the first one, a carbonaceous carbon material is used to deposite graphene over a substrate and, in the second one, graphite is used as raw material to obtain graphene using different methods. Inside the top down strategy, exfoliation of carbon nanomaterials, both graphite and graphene oxide, is considered as a cheap and simple method to synthesize graphene. Graphite exfoliation can be conducted with both aqueous and organic methods. On the other hand, different alternatives to produce graphene using graphene oxide as the raw material can be followed, which are based on either the presonication of graphite, as a previous step for manufacturing graphene, or the sonication of the synthesized graphite oxide, leading to graphene oxide.