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Showing papers on "Nickel boride published in 2018"


Journal ArticleDOI
TL;DR: This study reports the highly efficient electrocatalytic oxidation of HMF to FDCA, using Ni foam modified with high-surface-area nickel boride (Nix B) as the electrode, and provides insight into the reaction pathway.
Abstract: The electrochemical oxidation of the biorefinery product 5-(hydroxymethyl)furfural (HMF) to 2,5-furandicarboxylic acid (FDCA), an important platform chemical for the polymer industry, is receiving increasing interest. FDCA-based polymers such as polyethylene 2,5-furandicarboxylate (PEF) are sustainable candidates for replacing polyethylene terephthalate (PET). Herein, we report the highly efficient electrocatalytic oxidation of HMF to FDCA, using Ni foam modified with high-surface-area nickel boride (Nix B) as the electrode. Constant potential electrolysis in combination with HPLC revealed a high faradaic efficiency of close to 100 % towards the production of FDCA with a yield of 98.5 %. Operando electrochemistry coupled to ATR-IR spectroscopy indicated that HMF is oxidized preferentially via 5-hydroxymethyl-2-furancarboxylic acid rather than via 2,5-diformylfuran, which is in agreement with HPLC results. This study not only reports a low-cost active electrocatalyst material for the electrochemical oxidation of HMF to FDCA, but additionally provides insight into the reaction pathway.

218 citations


Journal ArticleDOI
TL;DR: A novel and self-standing amorphous ultrathin nanosheet of bimetallic iron-nickel boride on Ni foam is presented, which displays a better oxygen-evolving activity compared to the precious-metal catalyst RuO2 and may be extended to other energy-conversion and storage technologies.
Abstract: A cost-effective and efficient electrocatalyst for the oxygen evolution reaction during the electrolysis of water is highly desired. In an effort to develop an economical material for replacing precious-metal-based catalysts, a novel and self-standing amorphous ultrathin nanosheet (NS) of bimetallic iron-nickel boride (Fe-Ni-B NSs) on Ni foam is presented, which displays a better oxygen-evolving activity compared to the precious-metal catalyst RuO2 . In 1.0 m KOH electrolyte solution, it requires an overpotential of only 237 mV to reach a current density of 10 mA cm-2 with a small Tafel slope of 38 mV dec-1 and shows prominent long-term electrochemical stability. A synergistic effect between highly abundant catalytically active sites on the 3D porous substrate improved the electron transport arising from the presence of highly negative boron, and the high conductivity of the substrate results in an outstanding electrocatalytic activity. The advanced catalytic activity, facile electrode fabrication, and low costs make it a potential oxygen-evolving material, which may be extended to other energy-conversion and storage technologies.

67 citations


Journal ArticleDOI
TL;DR: In this paper, noble metals have been extensively used as catalyst promoters to drive highly efficient photocatalytic hydrogen evolution reaction (HER), however, noble metal-based promoters are limited by their...
Abstract: Noble metals have been extensively used as catalyst promoters to driven highly efficient photocatalytic hydrogen evolution reaction (HER). However, noble-metal-based promoters are limited by their ...

51 citations


Journal ArticleDOI
01 Oct 2018-Carbon
TL;DR: In this paper, a facile method for the in-situ incorporation of carbon dots into mesoporous nickel boride and their subsequent use as photcatalysts is presented.

43 citations


Journal ArticleDOI
TL;DR: Li et al. as mentioned in this paper incorporated nickel boride (Ni2B) nanoparticles into bulk graphitic carbon nitride (g-C3N4) to enlarge the specific surface area, exfoliate the layers, and improve the electronic conductivity.
Abstract: Graphitic carbon nitride (g-C3N4) functioning as a semiconductor catalyst and sustainable and clean energy carrier to substitute fossil energy is gaining the attention of researchers. Hydrogen is regarded as the right energy carrier to meet future conditions, and hence, developing hydrogen economy is intensively investigated for its great electrocatalytic property. However, it is blocked as an electrocatalyst due to its poor conductivity and electrochemical activity. Therefore, to conquer such shortcomings, changing the nanostructure and increasing active sites are studied. Here, we report a facile method by incorporation of nickel boride (Ni2B) nanoparticles into bulk g-C3N4 to enlarge the specific surface area, exfoliate the layers, and improve the electronic conductivity. The obtained catalysts exhibit better hydrogen evolution reaction (HER) performance with a low onset overpotential of 300 mV, a Tafel slope of 221 mV dec–1, and an overpotential of 707 mV at the current density of 10 mA cm–2, superior...

40 citations


Journal ArticleDOI
TL;DR: In this article, the scratch tests were performed over the surface of the nickel boride layer-substrate systems using a Rockwell-C diamond indenter with a continuously increasing normal force from 1 to 80 n, whereas the behavior of the coefficient of friction and the residual depth as a function of the scratch length were monitored during the tests.
Abstract: New results about the scratch adhesion resistance of nickel boride layer on Inconel 718 superalloy were estimated in the present study. The nickel boride layer was developed on the surface of Inconel 718 superalloy by means of the powder-pack boriding process conducted at 1173 K with 2, 4, and 6 h of exposure. The microstructure of the nickel boride layer was analyzed from optical microscopy, X-ray diffraction and energy dispersive spectroscopy (EDS). Furthermore, and before the scratch tests, indentation properties of the nickel boride layers such as hardness, Young's modulus, and the distribution of residual stresses were evaluated using Berkovich nanoidentation tests applying a constant load (50 mN) across the diffusion layers. The scratch tests were performed over the surface of the nickel boride layer-substrate systems using a Rockwell-C diamond indenter with a continuously increasing normal force from 1 to 80 N, whereas the behavior of the coefficient of friction and the residual depth as a function of the scratch length were monitored during the tests. For the determination of the critical loads, the combination of acoustic emission signal with microscopic observations of the worn tracks were used; the critical loads were estimated at which the layer cracks (cohesive failure) or is detached (adhesive failure) and they explained according to the mechanical properties of the nickel boride layer-substrate system. For all the set of experimental conditions, the presence of three types of failure mechanisms over the worn tracks were detected, while the results showed that the critical loads increase with enhancing nickel boride layer thickness.

32 citations


Journal ArticleDOI
TL;DR: In this paper, a hierarchical porous electrocatalyst structure utilizing Ni(OH)2 nanosheets directly synthesized on Ni foam as the conductive and interconnected supports was developed, which exhibited dramatically enhanced electrocatalytic activities and durabilities towards OER.
Abstract: Earth‐abundant and highly‐efficient electrocatalysts for oxygen evolution reaction (OER) are urgently desired to realize the large‐scale storage and conversion of renewable energies. In this work, we develop a hierarchical porous electrocatalyst structure utilizing Ni(OH)2 nanosheets directly synthesized on Ni foam as the conductive and interconnected supports. By coupling with amorphous Ni−B nanoparticles, this hybrid catalyst exhibits dramatically enhanced electrocatalytic activities and durabilities towards OER. In specific, along with the optimized Ni−B loading, this catalyst requires only an impressively small overpotential of 300 mV to drive a current density of 100 mA cm−2 for oxygen evolution in 1 M KOH electrolyte. Meanwhile, it also yields a small Tafel slope of 49 mV dec−1 and a superior long‐term stability. All these results evidently indicate that the hierarchical hybridization of Ni−B with Ni(OH)2 on Ni foam can effectively synergize the oxygen evolution, opening up a new vista for designing high‐performance transition metal‐based nanostructures in the field of electrochemical water splitting.

19 citations


Journal ArticleDOI
TL;DR: In this paper, the authors reported a simple synthesis of four new nickel boride-based nanocomposites from commercially available and cheap starting materials, namely Ni2B@ZrCl4, Ni2C@Cu2O, NiB@CuCl2 and Ni2D@FeCl3.
Abstract: In this paper, we report a simple synthesis of four new nickel boride-based nanocomposites, namely Ni2B@ZrCl4, Ni2B@Cu2O, Ni2B@CuCl2 and Ni2B@FeCl3, from commercially available and cheap starting materials. All of the new Ni2B-based nanocomposites were well characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Further, the catalytic applications of these new nanocomposites were successfully evaluated in the wet-solvent-free reduction of aromatic nitro compounds to arylamines with sodium borohydride (NaBH4) at room temperature by a mechanochemical grinding technique. All the introduced catalytic systems provide excellent yields of arylamines in very short reaction times for a wide range of substrates. Also, recoverability and reusability of the new nanocomposites were investigated.

19 citations


Journal ArticleDOI
TL;DR: In this paper, a synthesis route of single-phase Ni3B powder was developed using high-energy ball milling of nickel and boron powder mixtures, where the milling duration was varied from 1 to 15min.
Abstract: In this work, a synthesis route of Ni3B, an attractive material for making heating elements and a promising component for catalysts, was developed using high-energy ball milling of nickel and boron powder mixtures. The milling duration was varied from 1 to 15 min. Ball milling led to partial dissolution of boron in the crystalline lattice of nickel and crystallite size refinement of nickel. Heating of the ball-milled mixtures at a constant rate led to thermal explosion, the indications of which were a rapid temperature rise and the formation of boride phases. The duration of ball milling was shown to influence the phase composition of the products of thermal explosion. The time of milling ensuring the formation of single-phase Ni3B was determined to be 7 min. The ignition temperature of thermal explosion decreased with the milling time: a decrease by more than 300 °C was observed for the mixture milled for 15 min relative to the non-milled mixture. The maximum temperature developed during thermal explosion increased in the mixture milled for 1 min relative to the non-milled mixture and then decreased with the milling time reaching the level of the non-milled mixture after 15 min of milling. The observed dependence of the maximum temperature on the milling time is related to the net effect of mixing uniformity improvement between the reactants and a partial transformation of the reaction mixtures into Ni(B) solid solutions and Ni3B during milling. The proposed synthesis route of a single-phase Ni3B powder has advantages of short processing time and low-energy consumption.

8 citations


Journal ArticleDOI
TL;DR: Incoloy 909 superalloy was treated at 950°C to form coatings of different chemical composition by thermochemical diffusion as discussed by the authors, and it was found that coating the alloy for 12 and 20'h increased the hardness of the alloy and therefore its wear resistance.
Abstract: Incoloy 909 superalloy was treated at 950°C to form coatings of different chemical composition by thermochemical diffusion. Packing of the samples in reactive powders lead to the formation of iron borides (Fe2B and FeB) together with nickel boride, NiB, and nickel silicide, Ni2Si, on the surface of the alloy depending on the exposure time. X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy analyses suggest that growth of the coatings is controlled by diffusion of reactive species into the metal structure. Microabrasion wear resistance of the coated specimens was studied at 1 N load for a fixed sliding speed of 0.11 m s−1 and it was compared against uncoated samples of the alloy. It was found that coating the alloy for 12 and 20 h increased the hardness of the alloy and therefore its wear resistance.

6 citations


Journal ArticleDOI
TL;DR: Synthesis of the ternary intermetallic MgNi3B2 is demonstrated using autogenous pressure from the reaction of NaBH4 with Mg and Ni metal powder and Morphologies and microstructures suggest that solid–gas and liquid–gas reactions are dominant mechanisms and that Ni-borides form at a lower temperature than Mg Ni 3B2.
Abstract: We demonstrate synthesis of the ternary intermetallic MgNi3B2 using autogenous pressure from the reaction of NaBH4 with Mg and Ni metal powder. The decomposition of NaBH4 to H2 and B2H6 commences at low temperatures in the presence of Mg and/or Ni and promotes formation of Ni-borides and MgNi3B2 with the increase in temperature. MgNi3B2 aggregates with Ni-boride cores are formed when the reaction temperature is >670 °C and autogenous pressure is >1.7 MPa. Morphologies and microstructures suggest that solid–gas and liquid–gas reactions are dominant mechanisms and that Ni-borides form at a lower temperature than MgNi3B2. Magnetic measurements of the core-shell MgNi3B2 aggregates are consistent with ferromagnetic behaviour in contrast to stoichiometric MgNi3B2 which is diamagnetic at room temperature.

Journal ArticleDOI
TL;DR: A variety of 1, 1,1-diacetates have been chemoselectively and efficiently deprotected to the corresponding aldehydes as well as reduced to corresponding alcohols in this article.

Patent
23 Feb 2018
TL;DR: In this article, a preparation method of a carbon dot hybridization mesoporous nickel boride photocatalyst is described, which has the advantages of simple process, easiness in control, high yield and the like.
Abstract: The invention discloses a preparation method of a carbon dot hybridization mesoporous nickel boride photocatalyst. According to the method, the carbon dot hybridization mesoporous nickel boride photocatalyst is prepared by the steps of citric acid solution preparation, nickel addition, hydrothermal reaction, pH (potential of hydrogen) value adjustment, sodium borohydride addition reaction and centrifugation. The preparation method of the carbon dot hybridization mesoporous nickel boride photocatalyst has the advantages of simple process, easiness in control, high yield and the like.

Journal ArticleDOI
TL;DR: In this article, the effects of pH, adsorbent dose, contact time, and initial dye concentration on the adsorption efficiencies of nickel/nickel boride nanoparticles were investigated.
Abstract: Resins coated with nickel/nickel boride nanoparticles were used to remove brilliant green, methyl violet, methylene blue, phenosafranine, and brilliant cresyl blue from water. The effects of pH, adsorbent dose, contact time, and initial dye concentration on the adsorption efficiencies were investigated. The point of zero charge for the adsorbent was pH 9.5. Isotherm studies were conducted using Langmuir, Freundlich, and Dubinin--Radushkevich models, and thermodynamic studies were also performed. Adsorption of the five dyes was found to obey the Langmuir isotherm model and was endothermic. The maximum adsorption capacities calculated from the Langmuir isotherm were 66.7, 88.5, 144.9, 56.2, and 147.1 mg/g for methylene blue, brilliant cresyl blue, methyl violet, phenosafranine, and brilliant green, respectively. E values obtained from the Dubinin--Radushkevich isotherm showed that the adsorption mechanism was chemical in nature. Furthermore, three kinetic models (pseudo first-order, pseudo second-order, and intraparticle) were investigated. The pseudo second-order kinetic model fit the five cationic dyes best.

Patent
15 May 2018
TL;DR: In this article, a preparation method of high-adhesion fluorocarbon coating was proposed, in which a base and the aluminum source lithium meta-aluminate are added to a self-made silicon source; nickel boride and lemon juice are added during hydrothermal reaction, the catalyst and cheating property of organic acids in the lemon juice enable metal ions in aluminum silicon molecular sieve to leave original lattice and enter the organic acids; tea polyphenols and microbes are then used to perform further modification on the molecular sieves and nano silica, so that
Abstract: The invention relates to the technical field of preparation of coatings, in particular to a preparation method of high-adhesion fluorocarbon coating. A base and the aluminum source lithium metaaluminate are added to a self-made silicon source; nickel boride and lemon juice are added during hydrothermal reaction; nickel boride is used as a catalyst, the catalyst and cheating property of organic acids in the lemon juice enable metal ions in aluminum silicon molecular sieve to leave original lattice and enter the organic acids; tea polyphenols and microbes are then used to perform further modification on the molecular sieve and nano silica, so that adhesion of the coating is improved; the nano silica can improve wear resistance of the fluorocarbon coating. Grape wine contains rich organic carboxylic acid and other active ingredients; by adding the grape wine to the fluorocarbon coating, adhesion of the fluorocarbon coating is further improved; phenols and ketones having natural antioxidant action can be added such that the final fluorocarbon coating has significantly improved aging resistance and has a promising application prospect.

Patent
04 May 2018
TL;DR: In this article, a nanoscale hydrotalcite is obtained through a hydrothermal method, organic acid and nickel boride are added while a hydro-thermal reaction is made.
Abstract: The invention relates to a preparation method for a biomass adhesive-free plate, and belongs to the technical field of artificial board preparation. The preparation method includes the steps that nanoscale hydrotalcite is obtained through a hydrothermal method, organic acid and nickel boride are added while a hydrothermal reaction is made, the nickel boride is used as a catalyzer, the chelating property of the organic acid enables parts of metal ions in the hydrotalcite to leave original crystal lattices to enter the organic acid, cavities are generated in the original crystal lattices of thehydrotalcite, the generated cavities enable adsorption activity of the hydrotalcite to be greatly improved, a self-made inflaming retarding fortifier is obtained, bagasse and alkali liquor are mixed to be subject to soda boiling, in the process, a large number of active groups are increased in the fiber surfaces, through increase of the active groups, the chemical bonding force of the bagasse fibers is increased, furfural generated in the hydrolytic process can be soaked into the hydrotalcite under the hot pressing effect, a physical anchoring structure is formed after curing is carried out, and the mechanical property of the adhesive-free plate is improved again.


Patent
18 Dec 2018
TL;DR: In this paper, a graphite phase carbon nitride modified by non-noble metal-based nickel boride and a preparation method for hydrogen production in graphite-phase carbon dioxide (G-C3N4) is presented.
Abstract: Relating to graphite phase carbon nitride and preparation methods thereof, the invention provides graphite phase carbon nitride modified by non-noble metal-based nickel boride and a preparation methodthereof. The invention solves the problems of low light energy utilization and low activity during photocatalytic water decomposition for hydrogen production in graphite phase carbon nitride (i.e. g-C3N4). The graphite phase carbon nitride modified by non-noble metal-based nickel boride is prepared by loading NiBx on g-C3N4, wherein the mass percentage content of NiBx relative to g-C3N4 is 0.5wt%, 2.0wt%, 5.0wt%, 8.0wt% or 10wt%. The graphite phase carbon nitride modified by non-noble metal-based nickel boride provided by the invention can be applied to the photocatalyst field.

Patent
01 May 2018
TL;DR: In this paper, a method for preparing high-bonding-strength inorganic adhesive for an concrete interface is presented, which comprises the steps of adopting bauxite and montmorillonite as raw materials and performing a reaction on the raw materials, organic acids and nickel boride under the conditions of a high temperature and high pressure.
Abstract: The invention relates to the technical field of building material preparation, in particular to a method for preparing high-bonding-strength inorganic adhesive for an concrete interface The method comprises the steps of: adopting bauxite and montmorillonite as raw materials, and performing a reaction on the raw materials, organic acids and nickel boride under the conditions of a high temperatureand high pressure, wherein nickel boride is adopted as a catalyst, and metal ions in the bauxite and montmorillonitethe are made to leave original crystal lattices and enter the organic acids throughthe chelating property of the organic acids, so that cavities are formed in the original lattices of the bauxite and montmorillonite; and performing high-temperature dehydration in a resistance furnace so as to remove oxygen atoms at vertexes of tetrahedral and octahedral structures of the bauxite is removed and form six-coordinate structures, wherein oxygen cavities are formed in the original positions of the oxygen atoms, and the adsorption activity of the bauxite and montmorillonite can be increased through the generation of the cavities The adsorption cohesion inside the inorganic adhesive prepared from the materials can be improved, and the adsorption strength of the adhesive and the concrete surface can be improved, so that the bonding strength of the inorganic adhesive for the concrete interface is improved