In the current paper, Nanostructured Nickel oxide (NIO) were synthesized by co-precipitation method using Nickel (II) Chloride Hexahydrate (NiCl2.6H2O) and sodium hydroxide (NaOH) as starting material. Structural, optical and magnetic properties of nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Atomic force microscope (AFM), UV–Vis absorption; Fourier transformed infrared (FTIR) and vibrating sample magnetometer (VSM) technique. The X-ray diffraction pattern studies revealed the NIO have a face-centered cubic (FCC) structure and confirmed the presence of high degree of crystallinity nature NIO nanoparticles that their average size is found to be 26 nm. The composition of nanostructures confirmed by analysis of FTIR spectra. The average size of the NIO nanoparticle observed from scanning electron microscopy images is found to be dimensions about 24 nm. Magnetic measurement confirmed the Nickel Oxide nanostructures superparamagnetic behavior at room temperature (RT) after calcinations.

The Cu doped NIO (NIO: Cu) nanoparticles were synthesized by coprecipitation method using NiCl2.6H2O, CuCl2.2H2O for Ni and Cu sources, respectively. Sodium hydroxide has been used as a precipitator agent. Effect of Cu doping agent on the structural and optical properties of nanostructures were characterized by XRD, SEM, AFM, spectrophotometry, FTIR and VSM techniques. XRD revealed that NIO: Cu has a FCC structure. Optical absorption spectra of the samples obtained using UV-Vis spectrophotometer shows a blue-shift when copper amount increase which indicates decreasing particle size. The study of magnetization property at room temperature shows weak ferromagnetic behavior of NIO: Cu nanoparticles. Hysteresis loops were show that magnetization increasing with Cu doping up to 13% and then with further doping decreasing.

The human life is faced with bacterial infections which are one of the major cause of prevalence and mortality. Antibiotics have long been the preferred therapy for bacterial infections due to their cost-effectiveness and efficacy. In the field of overcoming microbial issues, new and emerging nanostructure-based materials have gotten a lot of attention. In this Study, NIO and sulfur, and nitrogen co doped-graphene quantum dots-decorated NIO nanocomposites (S,N-GQDs/NIO) are prepared via a simple hydrothermal method. Structural and morphological properties of products are determined via XRD, SEM, UV-Vis, and FTIR analysis. The prepared products are applied for the investigation of antibacterial activity against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and methicillin resistant Staphylococcus aureus (MRSA). The results showed that prepared S,N-GQDs/NIO nanocomposites have high antibacterial activity against Staphylococcus aureus among a wide range of microorganisms. For S,N-GQDs/NIO nanocomposites nanoparticles, the disk diffusion test proved that the highest growth inhibition zone was related to Staphylococcus aureus (17 mm). The presence of graphene quantum dots in S,N-GQDs/NIO nanocomposites facilitates reactive oxygen species (ROS) mechanism which lead to bet antibacterial activity.

Photocatalyst process as a green method can help significantly remove water pollutants. In his regard, various nanostructures can be applied as a photocatalyst for photodegradation of different dyes. In his work, zinc oxide nanoparticles (ZnO NPs), nickel oxide nanoparticles (NIO NPs), and zinc oxide/nickel oxide nanocomposites (ZnO/NIO nanocomposites) were synthesized through facile and simple co-precipitation route. The polyvinylpyrrolidone (PVP) was applied as a capping agent for controlling of particle size. The crystallinity and morphological properties of prepared products were studied via X-ray diffraction pattern (XRD) and scanning electron microscope (SEM) analysis. The optical band gaps of prepared ZnO NPs, NIO NPs, ZnO/NIO nanocomposites were calculated 3.16 eV, 3.43 eV, and 2.94 eV via UV-Vis-assisted plotting of the (αhν)² versus photon energy (hν). The obtained products applied as photocatalyst material for phodegradation of acid violet and rhodamine B (RhB). Also, catalyst dosage (0.03, 0.06, and 0.09 g) as an important parameter choose to investigate in the designed photocatalytic process. It is found that prepared ZnO NPs, NIO NPs, and ZnO/NIO nanocomposites shows excellent photocatalytic activity, although ZnO/NIO nanocomposites provided better removal (93.8%) compared to ZnO NPs (86.1%) and NIO NPs (81.5%) toward acid violet. The same trend was observed for rhodamine B. The results confirm that 0.06 g is the optimum dosage of catalyst.

In this study, efficiency of UV/NIO system as a forms of Advanced Oxidation Processes (AOP) to remove red poly azo was investigated. This study was conducted as a pilot scale and batch mode. Ultraviolet was achieved by 11 W low pressure lamp. Effects of various factors such as pH, different times of irradiation, different concentration of nickel oxide, primary concentration of colors were evaluated. The test results of UV/NIO system showed that no effects were observed with UV alone in photocatalysis process for removal of dye DR 80. Nickel oxide is an effective catalyst in removal of dye by the nanophotocatalytic process. The results represent that the color removal efficiency increase with pH reduction and optimum pH was found 4. Fainally, the highest removal efficiency for DR 80 dye with concenteration of 25 mg/L and 50 mg/L was obtained about 94.29% and 82.22% by the process of UV/NIO respectively. Reaction kinetic in the UV/NIO process follows pseudo secondry-order reactions. Totally UV/NIO process is an effective methode for DR 80 poly azo dye removal in aqueous solutions.

In this research the Hubbard parameters have been calculated for NIO and Gd crystals, as two strongly correlated systems with partially full 3d and 4f levels, respectively. The calculations were performed within the density functional theory (DFT) using the augmented plane waves plus the local orbitat (APW+lo) method. We constructed a suitable supercell and found that the Hubbard parameters for the NIO and Gd compounds are equal to 5.9 eV and 5.7 eV, respectively. Our results are in good agreement with experimental data and results of other computational methods.Then we used the obtained parameters to study the structural properties of NIO and Gd by means of LDA+U approximation. Our results calculated by the LDA+U method which are in better agreement with the experiment show a significant improvement compared to the GGA approximation. The result shows that our method for calculating U parameter can be considered as a satisfactory method to study a strongly correlated system.

This paper reports on the electrical and nanostructural properties of polymer-based materials in corporation with NIO (Nickel oxide) in weight concentrations of 0. 2%, 0. 4%, and 0. 8% of PVA (polyvinyl alcohol) polymer. Nanocrystallite phases and properties were characterized by using X-ray diffraction (XRD), Fourier transfer infrared (FTIR) radiation, scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. The dielectric constant of the samples has been calculated through measuring the capacity of the samples by application of GPS 132 A. Electrical property characterization was also performed with cyclic-voltameter (C-V) technique in TRIS solution; pH = 7. 3, with the formula (HOCH2)3CNH2.