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Graphite oxide was prepared by improved Hummer’s method. Then the graphene oxide (GO) suspension was obtained through ultrasonication for 1 h. The GO suspension was mixed with sulfur (S) using three different methods (namely sodium polysulfide route, sodium borohydride route, and hydrothermal route) of which two were chemical methods while one was hydrothermal method to make the composite material of reduce GO and sulfur (rGO–S). The electrode of the rGO–S composite was then prepared by making a slurry of active material, carbon black and polyvinylidene fluoride (PVDF). The sample of GO was analyzed using UV–visible and FTIR spectroscopy, while the sample of rGO and S was analyzed using XRD. This confirmed the synthesis of rGO–S for all the three methods. The comparison of all the three methods shows that the chemical methods are time consuming, difficult and toxic while hydrothermal method is easy and friendly.

The electrochemical properties of poly sodium 4-styrenesulfonate intercalated graphite oxide (PSSGO) have been investigated in a 1 M H₂SO₄ electrolyte. We observed capacitor behavior at scan rate of 1–25 mV/s in a cyclic voltammetry. Specific capacitance obtained from galvanostatic charge and discharge measurements were 6 F/g to 102 F/g at 1 A/g to 0.1 A/g, respectively. The specific capacitance of PSSGO is relatively high compared to that of the precursor graphite oxide in which the specific capacitance was 11–20 F/g at 0.03 A/g. Capacitance retention was 73% after 3000 cycles, proving reliable cyclic stability up to 3000 cycles.

GO/Cu₂O nanocomposite had been successfully synthesized by electrostatic interactions method. X-ray powder diffraction (XRD), transmission electron microscope (TEM), selective-area electron diffraction (SAED), Fourier transform infrared spectroscopy (FT-IR) and Raman spectra confirmed the structure of the Cu₂O and GO/Cu₂O nanocomposite. The catalytic degradation of Rhodamine B under the condition of ultrasound was investigated and the result of UV-Vis spectroscopy demonstrated that the nanocomposite can efficiently degraded it.

The graphite oxidation samples with different degrees of oxidation were prepared from natural flake graphite via a modified Hummers method with controlled addition of KMnO₄. The evolution of oxygen-containing functional groups was analyzed by Fourier transform infrared spectrometry (FT-IR) and X-ray photoelectron spectroscopy (XPS). The evolution rule of three-dimensional (3D) graphite structures during oxidation has been verified via X-ray diffraction (XRD). Experimental results show that the evolution of the interplanar spacing of samples during oxidation can be approximately divided into four stages. When the dosage of KMnO₄ is 0.5 g per 1 g of graphite (g/g), a graphite intercalation compound (GIC) is formed through intercalating reactions, and a slight increase is observed in the values of d₁₀₀ and d₁₁₀, suggesting that the π–π interactions which decrease the length of carbon–carbon bonds were partially disrupted. Adding additional KMnO₄ initiates the second stage, in which GIC begins to oxidize. The insertion of oxygen-containing functional groups in the graphene basal plane leads to dramatic changes in the values of d₁₀₀ and d₁₁₀. The d₁₀₀ is greatly reduced while d₁₁₀ increases slightly. These trends are attributed to the fact that the basal plane is stretched during the oxidation process. Further addition of KMnO₄ in the third stage leads to relatively small increases in the values of d₁₀₀ and d₁₁₀. This result is consistent with the evolution rule of hydroxyl groups. In this research, the evolution rule of the value of d₀₀₁ is also clearly demonstrated. When the concentration of KMnO₄ is not more than 3.0 g/g, the value of products d₀₀₁ keeps gradually increasing, indicating that oxygen-containing groups continue to form bonds with carbons in the basal plane, and that additional water molecules are adsorbed between the layers of the samples. All the interplanar spacing values (d₀₀₁, d₁₀₀ and d₁₁₀) are reduced significantly in the fourth stage, when the amount of KMnO₄ added up to 4.0 g/g. FT-IR and XPS analyses demonstrate that the decrease in the values of d₁₀₀ and d₁₁₀ is due to a reduction in the content of external hydroxyl groups. The change in d₀₀₁ is attributed to the partial release of water molecules confined in the interlayer spaces between adjacent sheets are partly released.

Nitro-oxidizers (nitric acid-27S, nitrogen tetroxide and mixed nitrogen oxide) are common liquid oxidants widely used in liquid rockets and missile weapons. How to deal with large quantities of scrapped nitro-oxidizers is a complex, costly and dangerous project. We pretreated it with hydrogen peroxide (H₂O${}_2)$ and converted the active oxidant component of nitro-oxidizers into nitric acid, which can be used as oxidant source to prepare graphite oxide from natural graphite. The comprehensive oxidation ability of the reaction system can be effectively controlled by adding different volumes of H₂O₂, and the oxidation ability can be expressed by the redox potential of the system. Combined with FT-IR, Raman and XRD characterization analysis, the optimal redox potential interval, [1700, 1800]mV, has been determined for the synthesis of graphite oxide. With the help of data interpolation and function nonlinear fitting and the initial potential of rejected nitro-oxidants obtained, the composition ratio of nitric acid and nitrogen tetroxide (N₂O${}_4)$ has been preliminarily determined with the optimum amount of H₂O₂. Furthermore, the optimum oxidizing atmosphere for the synthesis of graphite oxide can be formed in spite of a wide range of concentrations of oxidant components, and the resulting graphite oxide has been proven to be a qualified and effective product.