Mixtures of NICKEL OXIDE and activated carbon (99% carbon) with stiochiometric ratio were milled for different times in a planetary ball mill. The stiochiometric ratio of mixture was prepared in an un-milled condition. The unmilled mixture and milled samples were subjected to thermogravimetric analysis (TGA) under an argon atmosphere and their solid products of the reduction reaction were studied using XRD experiments. TGA showed that the reduction of NiO started at ~800℃ and ~720℃ in un-milled and one-hour milled samples respectively whilst after 25 h milling it decreased to about 430℃ . Increasing the amount of carbon more than stiochiometric ratio did not effect on the kinetics of carbothermic reduction. Thermodynamics assessments for NiO-C system were done using HSC software. Thermodynamics assessment and the experimental results indicated that Boudouard reaction plays a significant role in the carbothermic reduction reaction of NICKEL OXIDE. The results revealed that formation and increasing of monOXIDE carbon gas (COg) can change the kinetic reaction mechanism into solid-gas mechanism which has the major effect on increasing the rate of reaction. The decrease in the particle size/crystallite size of the NICKEL OXIDE in the milled samples not only resulted in decreasing in the reaction temperature, but also resulted in formation of fine particles of metallic NICKEL. Therefore, it is possible to achieve the metallic NICKEL particle in the range of submicron or nanometer via carbothermic reduction reaction of NiO using mechanical activation of NiO-C mixture.

This study introduced a novel, nontoxic, scalable, two-step method for the fabrication of NICKEL-NICKEL OXIDE foam/electrochemically reduced graphene OXIDE (ERGO) electrodes. This procedure included drop cast and graphene OXIDE (GO) reduction by constant current and pulse current methods. The result of structure was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy. Electrochemical impedance spectroscopy (EIS) measurements are carried out to study the electrochemical behavior of ERGO/Ni-NiO foam electrodes. SEM images revealed that the wrinkling degree of the synthesized graphene layers increased in pulse current method. The Raman test results showed that the current density pulse method is more efficient in comparison with constant current method. The XRD also showed that the interlayer spacing between the graphene sheets was higher in the pulse current method. The ERGO/Ni-NiO foam fabricated by pulse current method provided the least ESR value, and thus the highest rate charge/discharge process. The desirable electrochemical performance of ERGO/Ni-NiO foam electrode was mainly attributed to its irregular porous structure provided a large specific area, short ion diffusion distances and transport pathways for electrons. High-performance ERGO/Ni-NiO foam hybrid electrode materials made it as a reliable and accessible candidate for application in electrochemical energy storage.

This paper investigates the applicability of NICKEL-NICKEL OXIDE metallic foams as current collector for supercapacitor. A simple galvanic displacement reaction was employed to fabricate dendritic Cu dealloyed nanoporous Ni-NiO foam. A comprehensive characterization of foams is presented and includes the analysis of their structural, chemical, and electrochemical properties. The process is studied under well-defined experimental conditions using XRD, SEM, electrochemical impedance spectroscopy (EIS) and galvanostatic charge and discharge (GCD). XRD results confirm the presence of NICKEL and NICKEL OXIDE phases. Also, in the SEM test, porosities were observed in the range of micro and dendrites in the nanoscale. The outcome of these experiments demonstrates that the Ni-NiO foam has a higher specific capacitance. The best specific capacitance for Ni-NiO foam was calculated 924 F/g at 1A/g. Ni-NiO foam maintains 81. 8% of its specific capacitance at a current density of 20 A/g and after 3000 cycles. The created foam electrode can be used as a current collector for the deposition of subsequent layers and is a candidate for use in supercapacitors.

Hydrothermal synthesis of NICKEL-chitosan hybrid has been accomplished using Ni(CH3COO)2, 4H2O, chitosan and water as starting material, template and solvent respectively, followed by calcination at 800 and 900˚ C to provide nanoporous NiO800 and NiO900. The solid products were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) techniques. NiO800 proved to be active for adsorption of Congo red with pseudo-second order kinetic model and adsorption isotherms, respectively fitted by Freundlich equation. NiO900 was also found to successfully catalyze the photodegradation of organic dye pollutants such as Congo red and methylene blue. The kinetic of photocatalytic behavior of NiO900 have proven to obey the first order and Langmuir– Hinshelwood model.

Graphene-based nanocomposites are newly emerged materials with a wide range of applications such as in supercapacitors electrode. The high conductivity and ability for passing electric current, makes Graphene an appropriate new item to be used in cells. Electroactive transition metal OXIDEs, owing fast reversible redox pairs, are used to store electrical charge. Furthermore, the Graphene/NiO nanocomposites can be used to improve the electrochemical properties of NiO. Here we report a new and facile route for synthesizing Graphene/NiO nanorods composite (GNC). High-quality few-layer Graphene/NiO nanorod composite (GNC) is synthesized via solvothermal method. Solution phase exfoliation of graphite is investigated in N-Methyl-Pyrrolidone (NMP). The existence of few-layer graphene is confirmed by Raman spectroscopy while presence of NiO is demonstrated by UV-Vis spectroscopy (UV) and X-ray diffraction (XRD) pattern. The Field Emission Scanning Electron Microscopy (FESEM) and X-ray diffraction (XRD) pattern also provide proof of GNC on graphene. Images indicate NiO nanorods with average diameter of 35 nm and 100 nm lengths, deposited on graphene.

In this study metal OXIDE nano powder namely NiO nanopowder was prepared .The produced metal OXIDE was characterized and used as potential adsorbent for the removal of Pb and Zn from aqueous solution. The rate of uptake of the Pb and Zn are rapid in the beginning and the time required for equilibrium adsorption is 120 min .The time of equilibrium as well as time required to achieve a definite fraction of equilibrium adsorption is independent of initial concentration. The results showed that the removal of Pb increased significantly as the pH increased from 2.0 to 6.0 and approach a plateau at pH range of 6.0-9.0., while the removal of Zn increased significantly as the pH increased from 2.0 to 9.0. The adsorption of pb onto NiO follows the Langmiur isotherm, while the adsorption of Zn onto NiO follows the Freundlish isotherm. The pseudo second order kinetic model provided good correlation for the adsorption of Pb onto NiO nanopowder while the pseudo first order kinetic model provided good correlation for the adsorption of Zn onto NiO nanopowder.

Polyimide/NICKEL OXIDE (polyimide/NiO) nanocomposite was successfully synthesized by sol gel technique, using Pyromellitic dianhydriede (PMDA), 4, 4-oxydianiline (ODA) and N, N-dimethylacetamide (DMAC) and 10 wt% NICKEL titanate nanopowders (NPs). Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM) were used to characterize the structure and properties of the obtained nanocomposite. The results indicated that the average size of polyimide/NiO nanocomposite were estimated 65nm. Saturation magnetizations results indicate that by adding of NiO nanoparticles in polyimide matrix, magnetization decreases. The superparamagnetic behavior for NiO nanoparticles and polyimide/NiO nanocomposite of 10 wt% is reported whereas Polyimide has diamagnetic behavior.

In this paper, plate-like NiO nanoparticles were prepared by one-pot solid-state thermal decomposition of NICKEL (II) Schiff base complex as new precursor. First, the NICKEL (II) Schiff base precursor was prepared by solid-state grinding using NICKEL (II) nitrate hexahydrate, Ni (NO3) 2.6H2O, and the Schiff base ligand N, N'-bis- (salicylidene) benzene-1, 4-diamine) for 30 min without using any solvent, catalyst, template or surfactant. It was characterized by Fourier Transform Infrared spectroscopy (FT-IR) and elemental analysis (CHN). The resultant solid was subsequently annealed in the electrical furnace at 450 oC for 3 h in air atmosphere. Nanoparticles of NiO were produced and characterized by X-ray powder diffraction (XRD) at 2q degree 0-140o, FT-IR spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD and FT-IR results showed that the product is pure and has good crystallinity with cubic structure because no characteristic peaks of impurity were observed, while the SEM and TEM results showed that the obtained product is tiny, aggregated with plate-like shape, narrow size distribution with an average size between 10-40 nm. Results show that the solid state thermal decomposition method is simple, environmentally friendly, safe and suitable for preparation of NiO nanoparticles. This method can also be used to synthesize nanoparticles of other metal OXIDEs.