Graphene oxide hummers’ method

Figure 5.7 Schematic illustration of Brodie s method, Staudenmaier s method and Hummers method for the synthesis of graphene oxide hy chemical oxidation techniques.

Table 1 summarizes a survey of the synthetic approaches and resulting capacitance values of graphene-based electrodes (see also Refs. [5-7, 11, 14, 31, 76-80] for a review of synthetic approaches). Natural graphite is the most commonly used starting material, while more atypical materials such as CNTs [46] and platelet carbon nanofibers [55] have also been used. The (modified) Hummers method [81] is the most mutual method for oxidation of carbon, while the Staudenmaier [82] and Brodie [83] methods have also been applied. Reduction of the oxidized graphite oxide nanosheets is often conducted with hydrazine. 

Bulk graphite oxide is best prepared from purified natural graphite using the Hummers method Hummers, W. S. Offeman, R. E. J. Am. Chem. Soc. 1958,80,1339. For the mechanical exfoliation of bulk graphene oxide into sheets within an aqueous medium, see Stankovich, S. Dikin, D. A. Dommett, G. H. B. Kohlhaas, K. M. Zimney, E. J. Stach, E. A. Finer, R. D. Nguyen, S. T. Ruoff, R. S. Nature 2006,442, 282. 

Fig. 10 The structure of graphene oxide produced by Hummers method and the modification to the structure produced base washing. (Reproduced with permission.)... 

Zou, Z.G., Yu, H.J., Long, F., Fan, Y.H., 2011. Preparation of graphene oxide by ultrasound-assisted hummers method. Chinese Journal of Inorganic Chemistry 27, 1753—1757. 

Researchers have focused more on the synthesis and reduction of graphene oxide because GO and reduced GO can be synthesized easily. GO is usually synthesized from the oxidation of graphite by strong oxidants based on the Brodie, Staudenmaier, or Hummers methods or some other modification of these methods. Hummers method has been more widely used and many modifications have been made to synthesize GO for designated appHcations (Tong et al., 2013). 

Graphene oxide (GO) was prepared via the modified Hummers method [46]. Briefly, 2 g of graphite powder and 1 g of NaN03 were mixed with 46 mL of concentrated H.,SO, at 0°C in ice bath. The mixture was stirred... 

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