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The great promise of the combination of urea oxidation reaction (UOR) with hydrogen evolution reaction (HER) to simultaneously achieve wastewater treatment and hydrogen production calls for the rational design of high‐performance electrocatalysts. Herein, the reconstruction with the formation of Ni2P and Mo2O72− on the surface can largely enhance the alkaline HER activity of P‐NiMoO4 by on‐site electrochemical activation strategy. Systematic experimental results indicate that the reconstruction process enables the exposure of additional Ni sites and the adjustment of hydrogen adsorption to facilitate HER kinetics. Ultimately, a highly efficient alkaline HER electrode with low overpotential of −48.9 mV for 10 mA cm−2 is achieved. More importantly, a UOR electrolyzer assembled with A‐P‐NiMoO4 as the cathode and P‐NiMoO4 as the anode exhibits impressive performance with a small cell voltage of 1.363 V for 10 mA cm−2. The application of the fabricated electrodes in a practical cell driven by a commercial dry battery (1.5 V) demonstrates efficient and stable hydrogen production, making the developed strategy promising for the rational design of highly active electrocatalysts for green hydrogen production. [ABSTRACT FROM AUTHOR]

The annual production of plastic waste is a serious ecological problem as it causes substantial pollution of the environment. Polyethylene terephthalate, a material usually found in disposable plastic bottles, is one of the most popular material used for packaging in the world. In this paper, it is proposed to recycle polyethylene terephthalate waste bottles into benzene-toluene-xylene fraction using a heterogeneous nickel phosphide catalyst formed in situ during the polyethylene terephthalate recycling process. The catalyst obtained was characterized using powder X-ray diffraction, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy techniques. The catalyst was shown to contain a Ni2P phase. Its activity was studied in a temperature range of 250–400 °C and a H2 pressure range of 5–9 MPa. The highest selectivity for benzene-toluene-xylene fraction was 93% at quantitative conversion. [ABSTRACT FROM AUTHOR]

Recently, two-dimensional phosphorene (2D BP) has become an ideal material for electrocatalysts due to its short charge transport distance, high carrier mobility and fully exposed surface active sites. However, the inadequate adsorption energy of oxygen-containing intermediates results in the sluggish reaction kinetics, and thus limits its practical application. In this paper, granular amorphous Ni2P on the surface of BP to construct Ni2P@ BP heterostructure were introduced, in order to improve its electrochemical stability and reaction activity. The results show that, compared with the pure BP and Ni2P catalysts, the Ni2P@ BP catalyst exhibits excellent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalytic activities with an overpotential of 167 and 186 mV at a current density of 10 mA/cm², respectively. As a bifunctional electrocatalyst, Ni2P@ BP requires only 1. 54 V applied bias (Vapp) to achieve a current density of 10 mA/cm². Finally, over 7% solar to hydrogen (STH) coversion efficiency is achieved assisting with a-Si:H/a-SiGe:H/ a-SiGe:H triple-junction solar cell, which is 95% higher than that of pure BP as a bifunctional electrocatalyst. [ABSTRACT FROM AUTHOR]

By combining the advantages of doping to change the electronic structure of molybdenum disulfide (MoS2), transition metal phosphides, and MXene, we proposed the idea of designing and preparing a new type of composite material, P-doped MoS2/Ni2P/Ti3C2Tx heterostructures (denoted as P@MNTC), to serve as the hydrogen evolution reaction (HER) catalyst of electrochemical water splitting. The as-prepared P@MNTC heterostructures show a significant HER activity with an overpotential of 120 mV at 10 mA cm–2 in alkaline electrolyte, with decreasing 105 and 125 mV compared with those of MoS2 and MXene, respectively. The density functional theory indicates that the P doping and synergy effect of Ti3C2Tx can enhance the activation of MoS2 and thus promote dissociation and absorption of H2O during HER process. This strategy provides a promising way to develop high-efficiency MoS2- and Ti3C2Tx-based composite catalysts for alkaline HER. [ABSTRACT FROM AUTHOR]

Cd0.5Zn0.5 S nanoparticles and Ni2P nano-lamellar were prepared by precipitation-hydrothermal and low temperature thermal phosphating method,respectively. Low-cost, well-dispersed,efficient non-noble metal phosphide-assisted Ni2 P/Cd0.5Zn0.5 S composites were synthesized by using ultrasonic cavitation effect. The samples were characterized via XRD,SEM, UV-vis, PL, and electrochemical testing. Using Na2S-Na2SO3 as sacrificial agent, the photocatalytic activity of the samples was evaluated under visible light(λ ≥420 nm) irradiation. The results showed that Ni2P significantly improved the photocatalytic hydrogen evolution of Cd0.5Zn0.5 S. For 10% Ni2P/Cd0.5Zn0.5 S, the photocatalytic hydrogen generation rates is 19. 133 mmol/(g • h), which is 2. 4 times higher than that of Cd0.5Zn0.5 S[7. 865 mmol/(g • h)]. Additionally, the hydrogen generation rate keeps 91 % of the initial value after seven photocatalytic cycles, which can be attributed to the fact that the composite material has better light absorption ability and lower band gap, while the active center and interface effect provided by Ni2P effectively promote the rapid migration and effective separation of photo-generated carriers. [ABSTRACT FROM AUTHOR]

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Summary: The photocatalytic hydrogen evolution of MnxCd1‐xS in pure water has been achieved through suitable modification methods and efficient co‐catalysts. This article presents the photocatalytic performance and reaction mechanism of a Ni2P‐modified P‐doped MnxCd1‐xS photocatalyst (PNIMCS). It possesses admirable photocatalytic H2 evolution ability both in pure water and trapping agent solutions. The co‐catalysts Ni2P and P doping make a significant contribution in facilitating the PNIMCS photocatalytic pure water splitting to hydrogen reaction. They make the ECB of PNIMCS more negative, lower the overpotential of the hydrogen evolution reaction, and also promote the separation and transfer of photogenerated h+ and e−, thus improving the hydrogen evolution performance of PNIMCS. [ABSTRACT FROM AUTHOR]

Transition metal phosphides (TMPs) are promising candidates for sodium ion battery anode materials because of their high theoretical capacity and earth abundance. Similar to many other P-based conversion type electrodes, TMPs suffer from large volumetric expansion upon cycling and thus quick performance fading. Moreover, TMPs are easily oxidized in air, resulting in a surface phosphate layer that not only decreases the electric conductivity but also hinders the Na ion transport. In this work, we present a general electrode design that overcomes these two major challenges facing TMPs. Using metal hydroxide and glucose as precursors, we show that the metal hydroxide can be converted into phosphide whereas the glucose simultaneously decomposes and forms carbon shell on the phosphide particles under a plasma ambient. Ni2P@C core shell structures as a proof-of-concept are designed and synthesized. The in situ formed carbon shell protects the Ni2P from oxidation. Moreover, the high-energy plasma introduces porosity and vacancies to the Ni2P and more importantly produces phosphorus-rich nickel phosphides (NiPx). As a result, the Ni2P@C electrodes achieve high sodium capacity (693 mAh·g−1 after 50 cycles at 100 mA·g−1) and excellent cyclability (steady capacity maintained for at least 1, 500 cycles). Our work provides a general strategy for enhancing the sodium storage performance of TMPs, and in general many other conversion type electrode materials that are unstable in air and suffer from large volumetric changes upon cycling. [ABSTRACT FROM AUTHOR]

Developing efficient and low‐cost electrocatalysts toward oxygen evolution reaction (OER) has been one of the key research topics for overall water splitting due to the increasing demand for regenerated and clean energy. Herein, we report Ni2P@NiFe LDH hierarchical heterostructures in‐situ grown on nickel foam with good conductivity, strong substrate adhesion, special interface engineering and synergistic effects, which enables superior OER performance with a low overpotential of 204 mV at 10 mA cm−2 and a small Tafel slope of 33 mV dec−1 in 1 M KOH solution. This peculiar hierarchical hybrid electrode also possesses excellent electrochemical stability and long‐term durability at the current density of 50 mA cm−2 in an alkaline medium. More importantly, the proposed synthetic strategy of hierarchical heterostructures in this work will provide a general path to the preparation of various metal hydroxide catalysts for highly efficient OER. [ABSTRACT FROM AUTHOR]

In this work, we have developed a simple one-step synthesis of Ni2P and CoP phosphides based on a carbonization process. The current approach uses glucose as a reductant instead of H2 and employs inert gas as feed gas. The Ni2P/C and CoP/C obtained by the glucose route showed higher CH4-CO2 reforming performance than corresponding phosphides prepared by traditional H2 reduction method, which should be attributed to the fact that the phosphides prepared by glucose route had higher surface areas and smaller particle sizes than the ones prepared by traditional method. [ABSTRACT FROM AUTHOR]

We present a one-step route for the preparation of nickel phosphide/carbon nanotube (Ni2P@CNT) nano-composites for supercapacitor applications using a facile, ultrafast (90 s) microwave-based approach. Ni2P nanoparticles could grow uniformly on the surface of CNTs under the optimized reaction conditions, namely, a feeding ratio of 30:50:25 for CNT, Ni(NO3)2 · 6H2O, and red phosphorus and a microwave power of 1000 W for 90 s. Our study demonstrated that the single-step microwave synthesis process for creating metal phosphide nanoparticles was faster and simpler than all the other existing methods. Electrochemical results showed that the specific capacitance of the optimal Ni2P@CNT-nanocomposite electrode displayed a high specific capacitance of 854 F · g−1 at 1 A · g−1 and a superior capacitance retention of 84% after 5000 cycles at 10 A·g−1. Finally, an asymmetric supercapacitor was assembled using the nanocomposite with activated carbon as one electrode (Ni2P@CNT//AC), which showed a remarkable energy density of 33.5 W · h · kg−1 and a power density of 387.5 W·kg−1. This work will pave the way for the microwave synthesis of other transition metal phosphide materials for use in energy storage systems. [ABSTRACT FROM AUTHOR]

Hydrogen production from gaseous fuels, such as natural or liquefied petroleum gas, for fuel cell application requires feedstock free of catalyst poisons. As sulfur is one of the main poisons, different methods are employed to remove sulfur species. We propose a process not requiring external hydrogen feed to the feedstock. The hydrogen for the hydrogenation of the sulfur species is obtained directly from the hydrocarbon matrix reacting on a zeolite catalyst. The result is a desulfurization process with considerably simplified process management and a superior process startup. [ABSTRACT FROM AUTHOR]

Ni2P nanospheres were prepared by an ultrafast (120 s), easy, and energy-efficient one-step microwave method. By controlling the reaction conditions and feed ratio, Ni2P nanospheres with novel nanostructures and ultra-high electrochemical properties were prepared. These nanospheres demonstrated a high specific capacitance of 404.2 F g−1 at 1 A g−1 and high cycling durability. They maintain 81% of their initial capacity after 2000 cycles at 6 A g−1. The optimum device based on Ni2P//AC showed an outstanding energy density of 27.2 Wh kg−1 and power density of 375 W kg−1. A method that is much faster and much more energy-efficient than other approaches was developed to produce transition metal phosphates without atmosphere protection. [ABSTRACT FROM AUTHOR]

The study of benzothiophene hydrodesulfurization reaction path contribute to clarifying the mechanism of hydrodesulfurization (HDS) of heavy oil. In this work, experiments and simulations were combined to study the reaction pathway of benzothiophene hydrodesulfurization catalyzed by Ni2P. In experimental part, Ni2P catalyst was prepared and characterized. Then, the catalytic property of the catalyst for benzothiophene hydrodesulfurization was evaluated. The substance types and contents in the liquid phase products were detected to verify the accuracy of the simulation results. Dmol3 module of the Materials Studio (MS) simulation software was used to simulate the adsorption and hydrodesulfurization of benzothiophene on the surface of Ni2P catalyst and explore the most probable reaction path. The results showed that the most stable adsorption configuration of benzothiophene on the surface of Ni2P was Ni-hcp. In addition, indirect desulfurization of benzothiophene was more advantageous than direct desulfurization. The most possible path for indirect desulfurization was Benzothiophene (BT) – Dihydrobenzothiophene (DHBT) – C8H9S2 – 2-phenylethyl mercaptan (PET) – Ethylbenzene (EB), while that of direct desulfurization was Benzothiophene (BT) – C8H7S2 – Styrene thiol (CMT) – Styrene (ST) – Ethylbenzene (EB). [ABSTRACT FROM AUTHOR]

Two types of mixed oxides of B2O3 and Al2O3 were prepared. Aluminum borates (ABx, x represents the B/(B + Al) ratio) were prepared by low-temperature thermal decomposition of aluminum nitrate and H3BO3 sustained by the simultaneous oxidation of an organic agent (glycerol), while B2O3-Al2O3 with B/(B + Al) ratio of 0.3 was obtained by incipient wetness impregnation of H3BO3 on a commercial γ-Al2O3 support. Tetrahedrally, pentahedrally, and octahedrally coordinated Al3+ cations were all present in AB0.3 with ratios of 10.9/21.3/67.8, while no pentahedrally coordinated Al3+ was observed in B2O3-Al2O3. B2O3 was enriched in the surface of AB0.3. The Ni2P phase was obtained by temperature-programmed reduction of a phosphate precursor with a P/Ni ratio as low as 1.2 supported over both AB0.3 (Ni-P(1.2)/AB0.3) and B2O3-Al2O3 (Ni-P(1.2)/B2O3-Al2O3). This suggests that the surface B2O3 inhibits the reaction between nickel phosphates and Al2O3, and thus facilitates the formation of Ni2P. The hydrodesulfurization (HDS) of dibenzothiophene (DBT) over the supported Ni2P catalysts occurred mainly by the direct desulfurization pathway, and Ni-P(1.2)/B2O3-Al2O3 was much more active than Ni-P(1.2)/AB0.3. These features make B2O3-Al2O3 a promising support for Ni2P catalysts. The HDS of DBT followed a pseudo-first-order kinetics over Ni-P(1.2)/B2O3-Al2O3, whereas over Ni-P(1.2)/AB0.3 it can be described by pseudo-zero-order kinetics. The pseudo-zero-order kinetics suggests a strong adsorption of DBT on Ni-P(1.2)/AB0.3, which could be responsible for its lower activity. [ABSTRACT FROM AUTHOR]

Self‐sustaining photocatalytic NO3− reduction systems could become ideal NO3− removal methods. Developing an efficient, highly active photocatalyst is the key to the photocatalytic reduction of NO3−. In this work, we present the synthesis of Ni2P‐modified Ta3N5 (Ni2P/Ta3N5), TaON (Ni2P/TaON), and TiO2 (Ni2P/TiO2). Starting with a 2 mM (28 g/mL NO3−−N) aqueous solution of NO3−, as made Ni2P/Ta3N5 and Ni2P/TaON display as high as 79% and 61% NO3− conversion under 419 nm light within 12 h, which correspond to reaction rates per gram of 196 μmol g−1 h−1 and 153 μmol g−1 h−1, respectively, and apparent quantum yields of 3–4%. Compared to 24% NO3− conversion in Ni2P/TiO2, Ni2P/Ta3N5 and Ni2P/TaON exhibit higher activities due to the visible light active semiconductor (SC) substrates Ta3N5 and TaON. We also discuss two possible electron migration pathways in Ni2P/semiconductor heterostructures. Our experimental results suggest one dominant electron migration pathway in these materials, namely: Photo‐generated electrons migrate from the semiconductor to co‐catalyst Ni2P, and upshift its Fermi level. The higher Fermi level provides greater driving force and allows NO3− reduction to occur on the Ni2P surface. [ABSTRACT FROM AUTHOR]

A series of nickel phosphide catalysts with adjustable Brønsted acid sites and Lewis acid sites has been prepared by liquid-phase method using bis(triphenylphosphine) nickel dichloride as "all-in-one" precursors. The catalysts were characterized by XRD, TEM, 31P magic angle spinning (MAS) NMR, XPS, and NH3-TPD; then, its catalytic performance was tested in the liquid-phase hydrodeoxygenation of furfural to 2-methylfuran. The full furfural conversion and the selectivity for 2-methylfuran of 91.2% and the good catalytic stability can be achieved over the Ni2P-1.00-300 catalyst under the optimal reaction conditions (1.5-MPa H2, 260 °C, 3 h), which is attributed to the synergy between Lewis acid sites and Brønsted acid sites. [ABSTRACT FROM AUTHOR]

This paper is a first detailed report of natural hexagonal solid solutions along the join Fe2P-Ni2P. Transjordanite, Ni2P, a Ni-dominant counterpart of barringerite (a low-pressure polymorph of Fe2P), is a new mineral. It was discovered in the pyrometamorphic phosphide assemblages of the Hatrurim Formation (the Dead Sea area, Southern Levant) and was named for the occurrence on the Transjordan Plateau, West Jordan. Later on, the mineral was confirmed in the Cambria meteorite (iron ungrouped, fine octahedrite), and it likely occurs in CM2 carbonaceous chondrites (Mighei group). Under reflected light, transjordanite is white with a beige tint. It is non-pleochroic and weakly anisotropic. Reflectance values for four COM recommended wavelengths are [Rmax/Rmin, % (λ, nm)]: 45.1/44.2 (470), 49.9/48.5 (546), 52.1/50.3 (589), 54.3/52.1 (650). Transjordanite is hexagonal, space group P62m; unit-cell parameters for the holotype specimen, (Ni1.72Fe0.27)1.99P1.02, are: a = 5.8897(3), c = 3.3547(2) Å, V = 100.78(1) ų, Z = 3. Dcalc = 7.30 g/cm³. The crystal structure of holotype transjordanite was solved and refined to R1 = 0.013 based on 190 independent observed [I > 2σ(I)] reflections. The crystal structure represents a framework composed of two types of infinite rods propagated along the c-axis: (1) edgesharing tetrahedra [M(1)P4] and (2) edge-sharing [M(2)P5] square pyramids. Determination of unit-cell parameters for 12 members of the Fe2P-Ni2P solid-solution series demonstrates that substitution of Ni for Fe in transjordanite and vice versa in barringerite does not obey Vegard's law, indicative of preferential incorporation of minor substituent into M(1) position. Terrestrial transjordanite may contain up to 3 wt% Mo, whereas meteoritic mineral bears up to 0.2 wt% S. [ABSTRACT FROM AUTHOR]

Highlights: Three-dimensional phosphorus@graphene is established as a negative electrode and Ni2P as a positive electrode for asymmetric supercapacitor. The supercapacitor shows higher performance than those of all Ni2P-based electrodes, which has an extended operating voltage window of 1.6 V, energy density of 41.66 Wh Kg−1 and rate capability of up to 88% after 5000 cycles. Supercapacitors have attracted much attention in the field of electrochemical energy storage. However, material preparation, stability, performance as well as power density limit their applications in many fields. Herein, a sponge-like red phosphorus@graphene (rP@rGO) negative electrode and a Ni2P positive electrode were prepared using a simple one-step method. Both electrodes showed excellent performances (294 F g−1 and 1526.6 F g−1 for rP@rGO and Ni2P, respectively), which seem to be the highest among all rP@rGO- and Ni2P-based electrodes reported so far. The asymmetric solid-state supercapacitor was assembled by sandwiching a gel electrolyte-soaked cellulose paper between rP@rGO and Ni2P as the negative and positive electrodes. Compared to other asymmetric devices, the device, which attained a high operating window of up to 1.6 V, showed high energy and power density values of 41.66 and 1200 W kg−1, respectively. It also has an excellent cyclic stability up to 88% after various consecutive charge/discharge tests. Additionally, the device could power commercial light emitting diodes and fans for 30 s. So, the ease of the synthesis method and excellent performance of the prepared electrode materials mat have significant potential for energy storage applications. [ABSTRACT FROM AUTHOR]

Unsupported phosphide catalysts of composition Ni2P and CoP are prepared in situ in the reaction medium from oil-soluble precursors in the course of hydrodeoxygenation of palmitic and stearic acids. The obtained catalysts are characterized by X-ray powder diffraction and X-ray photoelectron spectroscopy; they show high activity in the hydrodeoxygenation of model substrates. After 6 h of the hydrodeoxygenation reactions, the conversion of palmitic acid reaches 93 and 92% and the conversion of stearic acid is as high as 94 and 91% in the presence of nickel phosphide and cobalt phosphide, respectively. It is shown that the catalyst formed in situ can be isolated and recycled. [ABSTRACT FROM AUTHOR]

We have studied P adsorption on Ni(111), a system which shows complex adsorbate structures. We determined the phase diagram of the surface P adsorbed on Ni(111). At low coverage, amorphous P was observed. At temperatures between 373 and 673 K and coverages above 0.1 monolayer, we found a 7 × 7 R 19.1 ∘ structure, but above 673 K, other complex structures were created. These structures seemed to correlate with each other and we reinterpret a 7 × 7 R 19.1 ∘ structure of P adsorbed on Ni(111) based on the similarities of these surface structures. The new rectangular structure for the 7 × 7 19.1 ∘ is discussed in relation to the Ni2P local structure. [ABSTRACT FROM AUTHOR]

A series of iron, cobalt and nickel metal phosphides of chemical formula FexP, Co2P and Ni2P with high specific surface areas of 331.1, 294.2 and 228.0 m2 g−1, respectively, was firstly synthesized by phenol-formaldehyde resin route. It was found that the as-prepared Co2P and Ni2P samples synthesized using phenol-formaldehyde resin as a carbon source showed much higher BET surface areas than those prepared using other carbon sources reported before, including cinnamic strong alkali anion exchange resin, p-phenylenediamine and hexamethylenetetramine. This phenol-formaldehyde resin route was proved to be as universal as traditional H2 reduction method. [ABSTRACT FROM AUTHOR]

A series of Ti-incorporated bulk Ni2P catalysts was prepared by means of temperatureprogrammed reduction, and the role of metallic Ti on the structure and catalytic activity of the Ni2P catalysts was studied. For this purpose, bulk Ni2P catalysts with metal Ti contents of 0.005 wt%, 0.01 wt%, and 0.02 wt% were synthesized. X-ray diffraction, CO uptake, Brunauer--Emmett--Teller measurements, and X-ray photoelectron spectroscopy were utilized to characterize the catalysts. Addition of titanium could increase the surface area and promote the formation of small, highly dispersed Ni2P particles. The Ti0.02-Ni2P system with a Ti molar fraction of 0.02 showed the highest hydrodesulfurization activity of 99.6%, which was an increase of 44% compared with that found for the bulk Ni2P. [ABSTRACT FROM AUTHOR]

The controlled synthesis of transition metal phosphides has been pursued to obtain excellent performances in application. Herein, we report a simple and effective method to synthesize nickel phosphide nanoparticles with target phases. Pure-phase nickel phosphide nanoparticles were obtained in different crystalline states (Ni2P and Ni12P5), and the crystalline phase of nickel phosphide could be controlled by varying the reaction conditions such as the temperature and duration of thermal treatment or the ratio between Ni and P. In addition, the nickel phosphide particles after thermal treatment maintained their sizes without serious agglomeration. In the hydrogenation of nitrobenzene, the phosphides with pure-phase (Ni2P or Ni12P5) and high crystallinity showed high catalytic activities. This proves that the crystalline phase of nickel phosphide plays an important role in the catalytic activity. [ABSTRACT FROM AUTHOR]

We have studied P adsorption on Ni(111), a system which shows complex adsorbate structures. We determined the phase diagram of the surface P adsorbed on Ni(111). At low coverage, amorphous P was observed. At temperatures between 373 and 673 K and coverages above 0.1 monolayer, we found a√7×√7 R19:1° structure, but above 673 K, other complex structures were created. These structures seemed to correlate with each other and we reinterpret a √7×√7 R19:1° structure of P adsorbed on Ni(111) based on the similarities of these surface structures. The new rectangular structure for the √7×√7 19:1° is discussed in relation to the Ni2P local structure. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen evolution is considered as one of the promising pathways to settle the energy crises and environmental issues by utilizing solar energy. In this paper, noble-metal-free Ni2P was used as cocatalyst to enhance g-C3N4 for photocatalytic hydrogen production under visible light irradiation (λ > 420 nm). Characterization results indicated that Ni2P nanoparticles were successfully loaded onto g-C3N4, which can significantly contribute to accelerate the separation and transfer of photogenerated electron. The hydrogen evolution rate reached ∼ 270 µmol h−1 g−1 and the apparent quantum yield (AQY) was ∼ 2.85% at 420 nm. Meanwhile, there is no obviously decrease of the hydrogen production rate even after 36 h under visible light illumination. In addition, the mechanism of photocatalytic hydrogen evolution was also elaborated in detail.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The γ‐Al2O3 supported Ni2P catalysts for propane dehydrogenation were prepared by one‐pot method and evaluated to study the platinum‐like behaviour of Ni2P. The catalysts were characterized by X‐ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy‐dispersive X‐ray Spectrometer (EDS), N2 adsorption at −196 oC and temperature‐programmed desorption of ammonia (NH3‐TPD). Results show that Ni2P is beneficial to the catalytic stability. It exhibits higher conversion for PDH of 23.8% and propylene selectivity of 74.4%. Ni2P was directly synthesised on the support γ‐Al2O3 to prepare the catalyst Ni2P/γ‐Al2O3. 20%Ni2P/γ‐Al2O3 shows a lasting high activity unlike 0.5%Pt/γ‐Al2O3 for 600 min. It exhibits conversion for PDH nearby 20% and propylene selectivity about 70% [ABSTRACT FROM AUTHOR]

Abstract: Sulfur cathodes have attracted significant attention as next‐generation electrode material candidates due to their considerable theoretical energy density. The main challenge in developing long‐life Li–S batteries is to simultaneously suppress the shuttle effect and high areal mass loading of sulfur required for practical applications. To solve this problem, we have designed a novel nickel phosphide nanoporous composite derived from metal–organic frameworks (MOFs) as sulfur host materials. Homogeneous distribution of Ni2P nanoparticles significantly avoids soluble polysulfides migrating out of the framework through strong chemical interactions, and the conductive 3D skeleton offers an accelerating electron transport. As a result, S@Ni2P/NC has exhibited an enhanced performance of 1357 mAh g−1 initially at 0.2 C (1 C=1675 mA g−1) and remaining at 946 mAh g−1 after 300 cycles. Even at an areal mass loading of sulfur as high as 4.6 mg cm−2, the electrode still showed an excellent specific capacity of 918 mAh g−1. [ABSTRACT FROM AUTHOR]

A novel and simple method to synthesize supported Ni2P/Na(x)-MCM-41 catalysts (where x is the mass fraction of Na-to-MCM-41 in terms of percentage) at a lower reduction temperature by incorporation of Na was described. The catalysts were characterized by H2 temperature-programmed reduction (H2-TPR), X-ray diffraction (XRD), N2 adsorption-desorption, CO uptake, X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The effect of Na on the structure of catalysts and catalytic properties for the dibenzothiophene (DBT) hydrodesulfurization (HDS) was investigated, which confirmed that a suitable amount of Na can promote highly dispersed Ni2P particles. The Na preferentially interacts with phosphate to generate the sodium phosphate and therefore suppresses the formation of stronger P-O-P bonds, which enables the phosphide catalyst to be easily formed at a lower reduction temperature. Compared with conventional phosphate (973-1273 K), the reduction temperature of Ni2P/Na(x)-MCM-41 catalyst was relatively low (773 K). The Ni2P/Na(x)-MCM-41 catalyst with x = 1.0 showed the maximum DBT conversion of 91.6%, which is higher than that of Ni2P/M41 without Na (80.3%). [ABSTRACT FROM AUTHOR]

Abstract: The hydrodenitrogenation (HDN) of quinolone (Q) and decahydroquinoline (DHQ) over a Ni2P catalyst prepared by the reduction of a conventional phosphate precursor and a surface nickel phosphosulfide phase (Ni2P-S) obtained by the reduction of Ni2P2S6 were studied. A reaction network of the HDN of Q over Ni2P was proposed. Both the hydrogenation and C-N bond cleavage activities of Ni2P were enhanced after the introduction of sulfur. The surface sulfur species of Ni2P-S changed significantly after the HDN of DHQ. The thiolate or thiol species were detected as the major sulfur-containing species in the surface of the spent Ni2P-S catalyst.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Highly active MCM-41-supported nickel phosphide catalysts for hydrodesulfurization (HDS) were synthesized by surface modification, in which the surface of supported Ni2P catalysts were directly modified at different temperatures by air instead of being passivated by an O2/N2 mixture. In addition, the prepared catalysts need not be activated under high temperature in H2 flow prior to the HDS reaction as in the conventional method. X-ray diffraction, X-ray photoelectron spectroscopy, N2-adsorption specific surface area measurements, CO chemisorption and transmission electron microscope were used to characterize the resulting catalysts. The effect of modification temperature on HDS performance of the catalysts was investigated. The results showed that the surface modification could promote the formation of smaller and more uniform Ni2P particles and the exposure of more Ni atoms. The modification method is simple and energy-saving, and the catalyst modified by air at 150 °C presents a dibenzothipohene conversion of 95.4%, which is 6.8% higher than that of a catalyst passivated by O2/N2 mixture followed by high-temperature and H2 pretreatments. [ABSTRACT FROM AUTHOR]

Amphiphilic phosphotungstic acid (A-PTA) and Ni2P/SBA-15 catalysts were prepared to apply for selective oxidation of refractory sulfur compounds in light cycle oils and hydrotreating of the oxidized S compounds, respectively. Physical properties of the catalyst samples were analyzed by BET, CO uptake chemisorption, and TEM. Structural properties for the supported Ni2P catalysts were analyzed by X-ray diffraction (XRD) and extended X-ray absorption fine structure (XAFS) spectroscopy. The selective oxidation of S compounds in the LCO feed was conducted in a batch reactor at H2O2/S ratio of 10, atmospheric pressure and 353 K and then the products were fed to a continuous flow fixed-bed reactor for hydrotreating at 623 K, 3.0 MPa, and LHSV's of 0.5-2.0 h-1. A-PTA catalyst showed a high oxidation conversion of 95% for a real LCO feed. The following hydrotreating led to a hydrodesulfurization (HDS) conversion of 99.6% and a hydrodenitrogenation (HDN) conversion of 94.7% over Ni2P/SBA-15, which were much higher than those of direct hydrotreating results which gave an HDS conversion of 63.5% and an HDN conversion of 17.5% based on the same LHSV of 2.0 h-1. It was revealed that the reduction in refractory nitrogen compounds after oxidative treatment contributed to the increase of the following HDS activity. [ABSTRACT FROM AUTHOR]

Developing efficient non-noble metal and earth-abundant electrocatalysts with tunable microstructures for overall water splitting is critical to promote clean energy technologies for a hydrogen economy. Herein, novel three-dimensional (3D) flower-like Ni2P composed of mesoporous nanoplates with controllable morphology and high surface area was prepared by a hydrothermal method and low-temperature phosphidation as efficient electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Compared with the urchin-like Ni xP y, the 3D flower-like Ni2P with a diameter of 5 μm presented an efficient and stable catalytic performance in 0.5 m H2SO4, with a small Tafel slope of 79 mV dec−1 and an overpotential of about 240 mV at a current density of 10 mA cm−2 with a mass loading density of 0.283 mg cm−2. In addition, the catalyst also exhibited a remarkable performance for the OER in 1.0 m KOH electrolyte, with an overpotential of 320 mV to reach a current density of 10 mA cm−2 and a small Tafel slope of 72 mV dec−1. The excellent catalytic performance of the as-prepared Ni2P may be ascribed to its novel 3D morphology with unique mesoporous structure. [ABSTRACT FROM AUTHOR]

A reliable strategy has been developed to prepare Ni2P nanofilms on carbon nanosheets (CNS) nanohybrids (Ni2P/CNS), which involves the preparation of three-dimensional (3D) CNS followed by in situ growth of Ni2P nanofilms on the surface of CNS. The Ni2P/CNS nanohybrids possess a robust 3D hierarchical structure, in which the Ni2P films are solidly overlaid on the surface of the CNS. The Ni2P/CNS nanohybrid was characterized by a variety of techniques, including X-ray diffraction (XRD), electron microscopy, X-ray photoelectron spectroscopy (XPS), etc. A series of electrochemical tests demonstrate the Ni2P/CNS nanohybrid shows high catalytic activity and excellent stability towards the hydrogen evolution reaction (HER) in pH-universal electrolyte, that is, in acidic, neutral, and basic media. The outstanding performance for Ni2P/CNS is correlated with the synergic effects between Ni2P and CNS associated with its unique and robust structure. [ABSTRACT FROM AUTHOR]

Ni2P nanoparticles supported by functionalized carbon nanotubes (CNTs) were prepared for the first time. Nickel (II) dihydrogenphosphite as a source of nickel, with different loadings on the functionalized CNTs, were used. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) techniques. Surface areas of the samples were measured by using Brunauer, Emmett and Teller (BET) method. The catalytic activity of the prepared samples was studied in hydrodesulfurization (HDS) of naphtha. The results showed that the CNTs were functionalized and Ni2P particles were dispersed on the functionalized CNTs. It was also indicated that the pores size of Ni2P particles were less than 20 nm. The catalytic study of the prepared samples confirmed that these compounds were stable and active in the process. Removal of sulfur from the desired naphtha in presence of the samples depended on the nickel loadings and increased with temperature in all cases. [ABSTRACT FROM PUBLISHER]

A series of SiO2 supported transition metal (Fe, Co, Ni, Mo and W) phosphide catalysts were synthesized and tested for the selective hydrogenation of cinnamaldehyde (CMA). Among these tested catalysts, Ni12P5/SiO2 and Ni2P/SiO2 prepared with initial Ni/P ratios of 2/1.3 and 1/1 exhibited high activity and selectivity for the conversion of CMA to hydrocinnamaldehyde (HCMA). The two nickel phosphide catalysts showed selectivity to HCMA up to 90% at a conversion of 90%. The properties of the nickel phosphide catalysts were characterized by BET surface area determinations, X-ray powder diffraction (XRD) analysis, and transmission electron microscopy (TEM). The influences of reaction temperature, hydrogen pressure, Ni/P ratio, and reduction temperature were studied in detail. For comparison, Pd/SiO2 catalyst was also used in this reaction, and the possible reasons for the different catalytic performances of the two kinds of catalysts are presented. [ABSTRACT FROM AUTHOR]

This work establishes the primordial role played by the support's nature when aimed at the constitution of Ni2P active phases for supported catalysts. Thus, carbon dioxide reforming of methane was studied over three novel Ni2P catalysts supported on Al2O3, CeO2 and SiO2-Al2O3 oxides. The catalytic performance, shown by the catalysts' series, decreased according to the sequence: Ni2P/Al2O3 > Ni2P/CeO2 > Ni2P/SiO2-Al2O3. The depleted CO2 conversion rates discerned for the Ni2P/SiO2-Al2O3 sample were associated to the high sintering rates, large amounts of coke deposits and lower fractions of Ni2P constituted in the catalyst surface. The strong deactivation issues found for the Ni2P/CeO2 catalyst, which also exhibited small amounts of Ni2P species, were majorly associated to Ni oxidation issues. Along with lower surface areas, oxidation reactions might also affect the catalytic behaviour exhibited by the Ni2P/CeO2 sample. With the highest conversion rate and optimal stabilities, the excellent performance depicted by the Ni2P/Al2O3 catalyst was mostly related to the noticeable larger fractions of Ni2P species established. [ABSTRACT FROM AUTHOR]

Highlights: Three-dimensional phosphorus@graphene is established as a negative electrode and Ni2P as a positive electrode for asymmetric supercapacitor. The supercapacitor shows higher performance than those of all Ni2P-based electrodes, which has an extended operating voltage window of 1.6 V, energy density of 41.66 Wh Kg−1 and rate capability of up to 88% after 5000 cycles. Supercapacitors have attracted much attention in the field of electrochemical energy storage. However, material preparation, stability, performance as well as power density limit their applications in many fields. Herein, a sponge-like red phosphorus@graphene (rP@rGO) negative electrode and a Ni2P positive electrode were prepared using a simple one-step method. Both electrodes showed excellent performances (294 F g−1 and 1526.6 F g−1 for rP@rGO and Ni2P, respectively), which seem to be the highest among all rP@rGO- and Ni2P-based electrodes reported so far. The asymmetric solid-state supercapacitor was assembled by sandwiching a gel electrolyte-soaked cellulose paper between rP@rGO and Ni2P as the negative and positive electrodes. Compared to other asymmetric devices, the device, which attained a high operating window of up to 1.6 V, showed high energy and power density values of 41.66 and 1200 W kg−1, respectively. It also has an excellent cyclic stability up to 88% after various consecutive charge/discharge tests. Additionally, the device could power commercial light emitting diodes and fans for 30 s. So, the ease of the synthesis method and excellent performance of the prepared electrode materials mat have significant potential for energy storage applications. [ABSTRACT FROM AUTHOR]

The effects of desilication (DS) of the zeolite β on the hydrocracking of polycyclic aromatics were investigated using the Ni2P/β catalysts. The Ni2P/β catalysts were obtained by the temperature-programmed reduction (TPR) method, and the physical and chemical properties were examined by N2 physisorption, X-ray diffraction (XRD), 27Al magic angle spinning–nuclear magnetic resonance (27Al MAS NMR), extended X-ray absorption fine structure (EXAFS), isopropyl amine (IPA) and NH3 temperature-programmed desorption (TPD), CO uptake, and thermogravimetric analysis (TGA). The catalytic activity was examined at 653 K and 6.0 MPa in a continuous fixed bed reactor for the hydrocracking (HCK) of model compounds of 1-methylnaphthalene (1-MN) and phenanthrene or a real feedstock of pyrolysis fuel oil (PFO). Overall, the Ni2P/DS-β was observed as more active and stable in the hydrocracking of polycyclic aromatics than the Ni2P/β catalyst. In addition, the Ni2P/β suffered from the coke formation, while the Ni2P/DS-β maintained the catalytic stability, particularly in the presence of large polycyclic hydrocarbons in the feed. [ABSTRACT FROM AUTHOR]

The development of non-noble metal hydrogen evolution catalysts that can replace Pt is crucial for efficient hydrogen production. Herein, we develop a type of well-dispersed Ni2P on N-doped nanomesh carbon (NC) electrocatalyst by a facile pyrolysis method, which shows excellent hydrogen evolution reaction (HER) catalytic performance. It is rather remarkable that the overpotential of Ni2P/NC prepared under optimal proportion is 108 mV at 10 mA·cm−2 current density in 1 M KOH solution with the tafel slope of 67.3 mV·dec−1, the catalytic activity has no significant attenuation after 1000 cycles of cyclic voltammetry (CV)method. The hydrogen evolution performance of the electrocatalytic is better than most similar catalysts in alkaline media. The unique mesh structure of the carbon component in the catalyst facilitates the exposure of the active site and reduces the impedance, which improves the efficiency of electron transport as well as ensuring the stability of the hydrogen evolution reaction. In addition, we prove that nitrogen doping and pore structure are also important factors affecting catalytic activity by control experiments. Our results show that N-doped nanomesh carbon, as an efficient support, combined with Ni2P nanoparticles is of great significance for the development of efficient hydrogen evolution electrodes. [ABSTRACT FROM AUTHOR]

For selective hydrogenation of chemicals the high selectivity is always at the expense of activity and improving both selectivity and activity is challenging. Here, by chelating with p‐fluorothiophenol (SPhF)‐arrays, both steric and electronic effects are created to boost the performance of cheap nickel‐based catalysts. Compared with dinickel phosphide, the SPhF‐chelated one exhibits nearly 12 times higher activity and especially its selectivity is increased from 38.1% and 21.3% to nearly 100% in hydrogenations of 3‐nitrostyrene and cinnamaldehyde. Commercial catalysts like Raney Ni chelating with SPhF‐array also exhibits an enhanced selectivity from 20.5% and 23.4% to ≈100% along with doubled activity. Both experimental and density functional theory (DFT) calculation prove that the superior performance is attributed to the confined flat adsorption by ordered SPhF‐arrays and downshifted d‐band center of catalysts, leading to prohibited hydrogenation of the vinyl group and accelerative H2 activation. Such a surface modification can provide an easily‐realized and low‐cost way to design catalysts for the selective hydrogenation. [ABSTRACT FROM AUTHOR]

Ni2P has been decorated on CdS nanowires or nanorods for efficient photocatalytic H2 production, whereas the specific surface area remains limited because of the large size. Here, the composites of Cd0.5Zn0.5S quantum dots (QDs) on thin Ni2P porous nanosheets with high specific surface area were constructed for noble metal-free photocatalytic H2 generation. The porous Ni2P nanosheets, which were formed by the interconnection of 15–30 nm-sized Ni2P nanoparticles, allowed the uniform loading of 7 nm-sized Cd0.5Zn0.5S QDs and the loading density being controllable. By tuning the content of Ni2P, H2 generation rates of 43.3 μM h− 1 (1 mg photocatalyst) and 700 μM h− 1 (100 mg photocatalyst) and a solar to hydrogen efficiency of 1.5% were achieved for the Ni2P-Cd0.5Zn0.5S composites. The effect of Ni2P content on the light absorption, photoluminescence, and electrochemical property of the composite was systematically studied. Together with the band structure calculation based on density functional theory, the promotion of Ni2P in charge transfer and HER activity together with the shading effect on light absorption were revealed. Such a strategy can be applied to other photocatalysts toward efficient solar hydrogen generation. [ABSTRACT FROM AUTHOR]