Facile synthesis of hierarchical nickel (III) oxide nanostructure: A synergistic remediating action towards water contaminants.

Heavy metal ion removal from consumable water is an indispensable need to maintain healthy life. Therefore cost effective and highly efficient sorbents are strongly needed to pose threat to real water pollution. Nanomaterials are widely used to maintain clean aqueous system in a very cost effective way with high removal efficiency. In this present work, pure coral like Ni2O3 nanostructures were prescribed for Cr(VI) remediation which were prepared by two step synthesis procedure at room temperature. The single hierarchical morphology as confirmed from HRTEM (size∼200 nm) were subjected to toxic Cr(VI) ion removal experiments. They were found to remove ∼65% Cr(VI) ions that was higher than that of pure Ni2O3 nanoparticles of comparable size. The enhanced properties were explained on the basis of the defect states present within the nanostructure, investigated by positron annihilation lifetime spectroscopy (PALS). It was found that the hierarchical nanostructure had more number of di-vacancies and vacancy-clusters as compared to the particles. On performing isotherm fitting, it was found that the coral like morphology had a high heterogeneity factor that aided to a high adsorption rate when compared to the pure Ni2O3 nanoparticles (which had a homogenous surface). The synthesized nanostructure was severely toxic to bacterial community having minimum inhibitory concentration (MIC) of ∼300 µg/L. Also the nanostructure exhibited dual functionality towards Cr(VI) and bacteria contaminated water at 200 µg/ml. The maximum Cr(VI) removal efficiency for this dual system is found to be 39% whereas antibacterial activity was turned out to be 30% which was extensively higher than that of toxic Cr(VI) ions. A plausible mechanism for the dual functionality was also predicted.

Photocatalytic removal of Congo red dye using MCM-48/Ni2O3 composite synthesized based on silica gel extracted from rice husk ash; fabrication and application.

MCM-48 mesoporous silica was successfully synthesized from silica gel extracted from rice husk ash and loaded by nickel oxide (Ni2O3). The resulted composite was characterized using X-ray diffraction, scanning electron microscope, and UV-vis spectrophotometer. The role of MCM-48 as catalyst support in enhancing the photocatalytic properties of nickel oxide was evaluated through the photocatalytic degradation of Congo red dye under visible light source. MCM-48 as catalyst support for Ni2O3 shows considerable enhancement in the adsorption capacity by 17% and 29% higher than the adsorption capacity of MCM-48 and Ni2O3, respectively. Additionally, the photocatalytic degradation percentage increased by about 64% relative to the degradation percentage using Ni2O3 as a single component. The adsorption mechanism of MCM-48/Ni2O3 is chemisorption process of multilayer form. The using of MCM-48 as catalyst support for Ni2O3 enhanced the adsorption capacity and the photocatalytic degradation through increasing the surface area and prevents the nickel oxide particles from agglomeration. This was done through fixing nickel oxide particles throughout the porous structure which providing more exposed active adsorption sites and active photocatalyst sites for the incident photons. Based on the obtained results, supporting of nickel oxide particles onto MCM-48 are promising active centers for the degradation of Congo red dye molecules.

Research on the Impact Initiation Behavior of PTFE/Al/Ni2O3 Reactive Materials.

PTFE/Al reactive material is an energetic material that releases energy under impact conditions, resulting in a wide range of application prospects. In order to improve its damage ability-considering the higher heat of the reaction per unit mass when Ni2O3 is involved in the aluminothermic reaction-we designed and studied PTFE/Al/Ni2O3, a reaction material based on polytetrafluoroethylene (PTFE). We also designed two other kinds (PTFE/Al, PTFE/Al/CuO) for comparative study, with the mass fraction of the metal oxides added at 10%, 20%, and 30%, respectively. The quasi-static compression properties and impact initiation behavior of the material were investigated by a universal material testing machine and a drop hammer test. The reaction process of different materials under a high strain rate was recorded using a high-speed camera. The results show that with the increase in Ni2O3 content, the strength of the PTFE/Al/Ni2O3 reactive material shows an increasing trend followed by a decreasing trend. Among the three reactive materials, when the content of Al/Ni2O3 reaches 30 wt.%, the reaction duration is the longest (at 4 ms) and the reaction fireball is the largest. The addition of Ni2O3 is helpful to improve the reactivity and reaction duration of the PTEF/Al reactive material.

Preparation and characterization of MCM-48/nickel oxide composite as an efficient and reusable catalyst for the assessment of photocatalytic activity.

Mesoporous silica (MCM-48) was synthesized and used as a catalyst for supporting the nickel oxide photocatalyst. The loading of nickel oxide on MCM-48 results in a considerable reduction in the bandgap energy to 2.4 eV. MCM-48 was used as a catalyst and back-supporter for the nickel oxide to enhance its photocatalytic properties along with adsorption capacity. Therefore, the adsorption capacity of MCM-48/Ni2O3 was enhanced by 17.5% and 32.2% compared to Ni2O3 and MCM-48, respectively. Furthermore, the percentage of photocatalytic degradation was improved by approximately 68.2% relative to the free-standing Ni2O3. The MCM-48/Ni2O3 proved the chemisorption adsorption mechanism that happens in multilayer form through the heterogeneous surface. This through fixing such Ni2O3 particles over the nanoporous topography to provide more exposed hot adsorption and photocatalytic sites for the incident light photons. Therefore, supporting Ni2O3 catalytic particles onto MCM-48 produces a new category of photocatalytic systems with promising active centers for the efficient degradation of Congo red dye molecules.

Fluorene Conjugated Polymer/Nickel Oxide Nanocomposite Hole Transport Layer Enhances the Efficiency of Organic Photovoltaic Devices.

A nanocomposite layer comprising the conjugated polymer poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctyl)fluorene] (PFN) and nickel oxide (NiOx) has been employed as the hole transport layer (HTL) in organic photovoltaics (OPVs) featuring PBDTTBO-C8 and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the active layer. The optimal device incorporating the PFN:NiOx nanocomposite as the HTLs displayed a power conversion efficiency (PCE) to 6.2%, up from 4.5% for the corresponding device incorporating pristine NiOx as the HTL layer: a nearly 40% improvement in PCE. X-ray photoelectron spectroscopy (XPS) was used to determine the types of chemical bonding, ultraviolet photoelectron spectroscopy (UPS) to measure the change in work function, and atomic force microscopy (AFM) to examine the morphology of the composite layers. The growth of nickel trioxide, Ni2O3, in the PFN:NiOx layer played a key role in producing the p-doping effect and in tuning the work function, thereby improving the overall device performance.

Novel gold nanocluster electrochemiluminescence immunosensors based on nanoporous NiGd-Ni2O3-Gd2O3 alloys.

Herein, three-dimensional nanoporous NiGd alloy (NP-NiGd) was prepared by selectively dealloy Al from NiGdAl alloy in mild alkaline solution, then Ni2O3 and Gd2O3 grew further on the surface of NP-NiGd to obtain the NP-NiGd-Ni2O3-Gd2O3. On this basis, NP-NiGd-Ni2O3-Gd2O3 was further functionalized with gold nanoparticles (NP-NiGd-Ni2O3-Gd2O3@Au) and acted as sensor platform to fabricate a novel electrochemiluminescence (ECL) immunosensor. Bovine serum albumin protected gold nanoclusters (AuNCs@BSA) were prepared and acted as illuminant. AuNCs@BSA modified graphene oxide (GO/AuNCs@BSA) were used as labels of second antibody. In order to characterize the performance of the ECL immunosensor, carcino embryonie antigen (CEA) was used as the model to complete the experiments. Due to the good performances of NP-NiGd-Ni2O3-Gd2O3@Au (high surface area, excellent electron conductivity) and AuNCs@BSA (low toxicity, biocompatibility, easy preparation and good water solubility), the ECL immunosensor exhibited a wide range from 10(-4) to 5ng/mL with a detection limit of 0.03pg/mL (S/N=3). The immunosensor with excellent stability, acceptable repeatability and selectivity provided a promising method to detect CEA in human serum sample sensitively.

THE PROTECTIVE EFFECTS OF VITAMIN C ON OXIDATIVE DAMAGE OF ALEVEOLAR MACROPHAGE INDUCED BY Ni2O3 IN VITRO / 营养学报

Objective:To study the effects of vitamin C (VC) on the injury of alveolar macrophages exposed to Ni2O3 in vitro and the expression of inducible nitric oxide synthase (iNOS). Method:The alveolar macrophages were cultured with exposure to Ni2O3 in vitro. Meanwhile,VC with different concentrations (25,50 and 100 ?mol/L) were added to the medium, respectively. The cell activity,nitric oxide(NO),reactive oxygen species (ROS), malondialdehyde (MDA) and activities of SOD, GSH-Px,CAT and iNOS were detected. iNOS mRNA expression was detected by using RT-PCR. Results:VC could decrease mortality and increase survival activity of alveolar macrophages. VC could also decrease ROS,NO and NOS activity,increase SOD,GSH-Px, CAT activities and downregulate the expression of iNOS mRNA. Conclusion:The lipid peroxidation of alveolar macrophage could be induced by Ni2O3. VC could downregulate the expression of iNOS mRNA and reduce the production of ROS and NO through increasing the activity of antioxidative enzymes and antagonize the oxidative damage induced by Ni2O3.