Great efforts have been paid to enhance the photoelectrochemical performances of LaFeO.sub.3. However, there have rarely been reported about modifying of LaFeO.sub.3 with transitional metal borides ...for enhanced photoelectrochemical activities. Herein, we prepared LFO/Ni-B composite electrodes by immersing LFO into the prepared electroless plating solution. The optimized LFO/Ni-B composite exhibits a 373% improvement of the photocurrent density and exhibits an anodic shift of onset potential. Systematic studies reveal that the improvement of PEC activity should be attributed to enhanced electrochemically active surface area and electrocatalytic properties, reduced resistance of the PEC system, and a more pronounced downward band bending at the photoelectrode/electrolyte interface. Graphic
Nickel is the most frequent cause of contact allergy worldwide and has been studied extensively. This clinical review provides an updated overview of the epidemiology, exposure sources, methods for ...exposure quantification, skin deposition and penetration, immunology, diagnosis, thresholds for sensitization and elicitation, clinical pictures, prevention, and treatment. The implementation of a nickel regulation in Europe led to a decrease in the prevalence of nickel allergy, and changes in the clinical picture and disease severity. Nevertheless, the prevalences of nickel allergy in the European general population are approximately 8% to 19% in adults and 8% to 10% in children and adolescents, with a strong female predominance. Well‐known consumer items such as jewellery and metal in clothing are still the main causes of nickel allergy and dermatitis, although a wide range of items for both private and occupational use may cause dermatitis. Allergic nickel dermatitis may be localized to the nickel exposure site, be more widespread, or present as hand eczema. Today, efficient methods for exposure quantification exist, and new insights regarding associated risk factors and immunological mechanisms underlying the disease have been obtained. Nevertheless, questions remain in relation to the pathogenesis, the persistent high prevalence, and the treatment of severe cases.
Nickel (Ni) is a worldwide pollutant and contaminant that humans are exposed to through various avenues resulting in multiple toxic responses — most alarming is its clear carcinogenic nature. A ...variety of particulate Ni compounds persist in the environment and can be distinguished by characteristics such as solubility, structure, and surface charge. These characteristics influence cellular uptake and toxicity. Some particulate forms of Ni are carcinogenic and are directly and rapidly endocytized by cells. A series of studies conducted in the 1980s observed this process, and we have reanalyzed the results of these studies to help elucidate the molecular mechanism of particulate Ni uptake. Originally the process of uptake observed was described as phagocytosis, however in the context of recent research we hypothesize that the process is macropinocytosis and/or clathrin mediated endocytosis. Primary considerations in determining the route of uptake here include calcium dependence, particle size, and inhibition through temperature and pharmacological approaches. Particle characteristics that influenced uptake include size, charge, surface characteristics, and structure. This discussion is relevant in the context of nanoparticle studies and the emerging interest in nano-nickel (nano-Ni), where toxicity assessments require a clear understanding of the parameters of particulate uptake and where establishment of such parameters is often obscured through inconsistencies across experimental systems. In this regard, this review aims to carefully document one system (particulate nickel compound uptake) and characterize its properties.
Porous Ni(OH)2 nanoflakes are directly grown on the surface of nickel foam supported Ni3Se2 nanowire arrays using an in situ growth procedure to form 3D Ni3Se2@Ni(OH)2 hybrid material. Owing to good ...conductivity of Ni3Se2, high specific capacitance of Ni(OH)2 and its unique architecture, the obtained Ni3Se2@Ni(OH)2 exhibits a high specific capacitance of 1689 µAh cm−2 (281.5 mAh g−1) at a discharge current of 3 mA cm−2 and a superior rate capability. Both the high energy density of 59.47 Wh kg−1 at a power density of 100.54 W kg−1 and remarkable cycling stability with only a 16.4% capacity loss after 10 000 cycles are demonstrated in an asymmetric supercapacitor cell comprising Ni3Se2@Ni(OH)2 as a positive electrode and activated carbon as a negative electrode. Furthermore, the cell achieved a high energy density of 50.9 Wh L−1 at a power density of 83.62 W L−1 in combination with an extraordinary coulombic efficiency of 97% and an energy efficiency of 88.36% at 5 mA cm−2 when activated carbon is replaced by metal hydride from a commercial NiMH battery. Excellent electrochemical performance indicates that Ni3Se2@Ni(OH)2 composite can become a promising electrode material for energy storage applications.
A facile method for general synthesis of core–shell structured Ni3Se2@Ni(OH)2 nanowires as a binder‐free electrode for asymmetric supercapacitors is described in this study. Due to the intimate contact between the materials, the core–shell structured Ni3Se2@Ni(OH)2 binder‐free electrodes provide a promising target structure for asymmetric supercapacitors.
The authors describe double-shell magnetic nanoparticles functionalized with 2-mercaptobenzothiazole (MBT) to give nanospheres of the type MBT-Fe.sub.3O.sub.4@SiO.sub.2@C). These are shown to be ...viable and acid-resistant adsorbents for magnetic separation of the heavy metal ions Ni(II), Cu(II) and Pb(II). MBT act as a binding reagent, and the carbon shell and the silica shell protect the magnetic core. Following 12 min incubation, the loaded nanospheres are magnetically separated, the ions are eluted with 2 M nitric acid and then determined by inductively coupled plasma-mass spectroscopy. The limits of detection of this method are 2, 82 and 103 ng Lâ¾.sup.1 for Ni(II), Cu(II), and Pb(II) ions, respectively, and the relative standard deviations (for n = 7) are 6, 7.8, and 7.4 %. The protocol is successfully applied to the quantitation of these ions in tap water and food samples (mint, cabbage, potato, peas). Recoveries from spiked water samples ranged from 97 to 100 %.
A versatile nickel catalyst allowed for CH alkylations of unactivated arenes with challenging secondary alkyl bromides and chlorides. The high catalytic efficacy also set the stage for direct ...secondary alkylations of indoles as well as CH trifluoroethylations with ample substrate scope. PUBLICATION ABSTRACT
High‐nickel LiNi1−x−yMnxCoyO2 (NMC) and LiNi1−x−yCoxAlyO2 (NCA) are the cathode materials of choice for next‐generation high‐energy lithium‐ion batteries. Both NMC and NCA contain cobalt, an ...expensive and scarce metal generally believed to be essential for their electrochemical performance. Herein, a high‐Ni LiNi1−x−yMnxAlyO2 (NMA) cathode of desirable electrochemical properties is demonstrated benchmarked against NMC, NCA, and Al–Mg‐codoped NMC (NMCAM) of identical Ni content (89 mol%) synthesized in‐house. Despite a slightly lower specific capacity, high‐Ni NMA operates at a higher voltage by ≈40 mV and shows no compromise in rate capability relative to NMC and NCA. In pouch cells paired with graphite, high‐Ni NMA outperforms both NMC and NCA and only slightly trails NMCAM and a commercial cathode after 1000 deep cycles. Further, the superior thermal stability of NMA to NMC, NCA, and NMCAM is shown using differential scanning calorimetry. Considering the flexibility in compositional tuning and immediate synthesis scalability of high‐Ni NMA very similar to NCA and NMC, this study opens a new space for cathode material development for next‐generation high‐energy, cobalt‐free Li‐ion batteries.
A novel cobalt‐free high‐energy cathode material, high‐nickel LiNi1−x−yMnxAlyO2 (NMA), is reported, with desirable physical and electrochemical properties. Benchmarked against LiNi1−x−yMnxCoyO2 (NMC) and LiNi1−x−yCoxAlyO2 (NCA) of identical Ni content (89 mol%), NMA delivers attractive specific energy, rate capability, cyclability, and thermal stability. Morevoer, NMA offers immediate synthesis scalability without the constraint of a vulnerable cobalt supply chain.
Breakthroughs toward effective water‐splitting electrocatalysts for mass hydrogen production will necessitate material design strategies based on unexplored material chemistries. Herein, Ni‐metalloid ...(B, Si, P, As, Te) alloys are reported as an emergent class of highly promising electrocatalysts for the oxygen evolution reaction (OER) and insight is offered into the origin of activity enhancement on the premise of the surface electronic structure, the OER activation energy, influence of the guest metalloid elements on the lattice structure of the host metal (Ni), and surface‐oxidized metalloid oxoanions. The metalloids modify the lattice structure of Ni, causing changes in the nearest Ni–Ni interatomic distance (dNi–Ni). The activation energy Ea scales with dNi–Ni indicating an apparent dependence of the OER activity on lattice properties. During the OER, surface Ni atoms are oxidized to nickel oxyhydroxide, which is the active state of the catalyst, meanwhile, the surface metalloids are oxidized to the corresponding oxoanions that affect the interfacial electrode/electrolyte properties and hence the adsorption/desorption interaction energies of the reacting species.
Compounds and alloys of nickel with the metalloids (B, Si, P, As, and Te) are emergent highly promising electrocatalysts for the oxygen evolution reaction (OER), however, the origin of their OER activity remains poorly understood. Insights into the origin of the OER activity enhancement in terms of their electronic and geometric properties and interfacial electrode–electrolyte interactions are presented.
Nickel: Human Health and Environmental Toxicology Genchi, Giuseppe; Carocci, Alessia; Lauria, Graziantonio ...
International journal of environmental research and public health,
01/2020, Volume:
17, Issue:
3
Journal Article
Peer reviewed
Open access
Nickel is a transition element extensively distributed in the environment, air, water, and soil. It may derive from natural sources and anthropogenic activity. Although nickel is ubiquitous in the ...environment, its functional role as a trace element for animals and human beings has not been yet recognized. Environmental pollution from nickel may be due to industry, the use of liquid and solid fuels, as well as municipal and industrial waste. Nickel contact can cause a variety of side effects on human health, such as allergy, cardiovascular and kidney diseases, lung fibrosis, lung and nasal cancer. Although the molecular mechanisms of nickel-induced toxicity are not yet clear, mitochondrial dysfunctions and oxidative stress are thought to have a primary and crucial role in the toxicity of this metal. Recently, researchers, trying to characterize the capability of nickel to induce cancer, have found out that epigenetic alterations induced by nickel exposure can perturb the genome. The purpose of this review is to describe the chemical features of nickel in human beings and the mechanisms of its toxicity. Furthermore, the attention is focused on strategies to remove nickel from the environment, such as phytoremediation and phytomining.
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