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Photocatalysis is a promising route to convert solar light into chemical energy for H 2 evolution and pollutants degradation. Hence, Ni 2 P decorated ZnCr 2 O 4 (Ni 2 P/ZnCr 2 O 4) nanofibers were prepared for boosting solar-light induced water splitting and tetracycline hydrochloride (TCH) degradation. For comparison to ZnCr 2 O 4 nanofibers, Ni 2 P/ZnCr 2 O 4 composites exhibited the better photocatalytic activities for water splitting and TCH removal. Owing to the co-catalytic effect of Ni 2 P for the efficient photon capture, the charge carriers were rapidly separated and migrated at the interface between Ni 2 P and oxygen-defected ZnCr 2 O 4. H 2 evolution rate of optimal C–Ni 2 P/ZnCr 2 O 4 with a nominal Ni 2 P content of 9.0 wt% was 575.89 μmol g−1 h−1, and its apparent quantum yield at 420 nm was 15.25 %, while its H 2 evolution decreased from 2815.13 to 2602.51 μmol g−1 after fifth cycle. In addition, the removal efficiency of C–Ni 2 P/ZnCr 2 O 4 was 93.68 % within 90 min, and declined to 88.76 % after five cycles for solar-light driven degradation of 50 mg L−1 TCH solution. The deactivation of C–Ni 2 P/ZnCr 2 O 4 was due to the photo-corrosion for the change in valence states of compositions. [ABSTRACT FROM AUTHOR]

The main prerequisite for designing electrocatalysts with favorable performance is to examine the links between electronic structural features and catalytic activity. In this work, Ni2P as a model electrocatalyst and one of the most potent catalysts for hydrogen evolution reaction (HER) was utilized to develop various Ni2P and carbon-based (graphene and N-doped graphene) heterostructures. The characteristics of such structures (Ni2P, graphene, N-doped graphene, Ni2P/graphene, and Ni2P/N-doped graphene), including binding energies, the projected density of states (PDOS), band structure, charge density difference, charge transfer, Hirshfeld charge analysis, and minimum-energy path (MEP) towards HER were calculated and analyzed by density functional theory (DFT) approach. The coupling energy values of hybrid systems were correlated with the magnitude of charge transfer. The main factors driving a promising water-splitting reaction were explained by the data of PDOS, band structures, and charge analysis, including the inherent electronegativity of the N species alongside shifting the Fermi level toward the conductive band. It was also shown that a significant drop occurs in the HER energy barrier on Ni2P/graphene compared to the pristine Ni2P due to N doping on the graphene layer in the Ni2P/N-doped graphene heterostructure.

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 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.

The bifunctional electrocatalyst Ni 2 P/NF was synthesized for highly efficient oxidation of benzyl alcohol (BA) and reduction of water, simultaneously. [Display omitted] • Ni 2 P/NF (Ni foam) is fabricated by facile one-step calcination, and the nickel foam acts as both the support and the nickel source. • The catalyst Ni 2 P/NF is bifunctional and can be applied in the cathode and anode simultaneously. • A series of electrochemical tests show that Ni 2 P has excellent benzyl alcohol (BA) electrooxidation and HER activity. • The theoretical calculation explains that the synergistic effect of Ni and P can reduce the energy barrier of the rate-determining process during BA oxidation. Considering the high costs of producing catalysts, designing a bifunctional catalyst is one of the favorable ways through which the best result can be achieved with less effort. Herein, we use a one-step calcination method to obtain a bifunctional catalyst Ni 2 P/NF for the simultaneous oxidation of benzyl alcohol (BA) and reduction of water. A series of electrochemical tests have shown that this catalyst has a low catalytic voltage, long-term stability and high conversion rates. The theoretical calculation unveils the essential reason for its excellent activity. The synergistic effect of Ni and P optimizes the adsorption and desorption energy of the intermediate species, thus reducing the energy barrier of the rate-determining step during BA electrooxidation. Thus, this work has laid the foundation for designing a highly efficient bifunctional electrocatalyst for BA oxidation and the hydrogen revolution. [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]

[Display omitted] • Mixtures of Ni(NO 3) 2 and H 3 PO 3 on SiO 2 and B 2 O 3 -Al 2 O 3 were used as precursors. • Reduction of the precursors yielded ultrasmall Ni 2 P particles (ca. 3 ∼ 5 nm). • Ni 2 P was formed on SiO 2 and B 2 O 3 -Al 2 O 3 at P/Ni ratios of 0.8 and 0.7, respectively. • Ultrasmall Ni 2 P particles on SiO 2 were as active as large Ni 2 P particles. • The strong Ni 2 P-support interaction inhibited the activity of Ni 2 P/B 2 O 3 -Al 2 O 3. Ultrasmall Ni 2 P nanoparticles with dimensions around 3 ∼ 5 nm supported on SiO 2 (Ni-P/SiO 2) and an Al 2 O 3 -B 2 O 3 mixed oxide (Ni-P/AB) were prepared by a temperature-programmed reduction method using mixtures of Ni(NO 3) 2 and H 3 PO 3 as precursors. The minimum P/Ni ratios of the precursors needed for the formation of phase-pure Ni 2 P on SiO 2 and Al 2 O 3 -B 2 O 3 were as low as 0.8 and 0.7, respectively. The introduction of B 2 O 3 to γ-Al 2 O 3 inhibited the formation of AlPO 4 during the reduction process. For such small particles, the effect of Ni 2 P-support interaction became significant, resulting in different properties of the Ni-P/SiO 2 and Ni-P/AB catalysts as well as different performances in the hydrodesulfurization of dibenzothiophene. The ultrasmall Ni 2 P nanoparticles in the Ni-P/SiO 2 catalysts that possess weak Ni 2 P-support interaction were as active as large Ni 2 P particles on SiO 2 and a macro-mesoporous Al 2 O 3. These catalysts were one order of magnitude more active than the Ni-P/AB catalysts with strong Ni 2 P-support interaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly dispersed Ni 2 P catalyst was prepared from nickel phyllosilicate precursor. • Nickel phyllosilicate facilitated the formation of nanosized Ni 2 P particles. • (2 0 1) plane of Ni 2 P gave more coordinately-unsaturated active sites. • Ni 2 P/SiO 2 -DP exhibited high performance in hydrodesulfurization of 4,6-DMDBT. • Highly dispersed Ni 2 P catalysts were obtained on MCM-41, S-1, and TS-1. Highly dispersed Ni 2 P catalysts were prepared from nickel phyllosilicate precursor, which was generated on the support by the deposition–precipitation (DP) method. Si-containing materials, including SiO 2 , MCM-41, S-1, and TS-1, were used as the supports. The strong interaction between Ni and Si species in nickel phyllosilicate effectively suppressed the agglomeration of nickel species. Highly dispersed Ni 2 P catalyst (Ni 2 P/SiO 2 -DP) was obtained by subsequent temperature-programmed hydrogen reduction, and the size of Ni 2 P crystallites was smaller than that of Ni 2 P/SiO 2 -IM prepared from conventional impregnation precursor (7.7 nm vs 14.2 nm). HRTEM observation demonstrated that a large fraction of (2 0 1) planes were present in Ni 2 P/SiO 2 -DP whereas (1 1 1) planes were predominant in Ni 2 P/SiO 2 -IM. The strong metal-support interaction and the smaller particle size, along with the higher degree of coordinately unsaturated sites facilitated the hydrogen spillover and the hydrogenation activity. As a result, Ni 2 P/SiO 2 -DP exhibited significantly higher performance than Ni 2 P/SiO 2 -IM in hydrodesulfurization of 4,6-dimethyldibenzothiophene. Similarly, highly dispersed Ni 2 P catalysts supported on Si-containing molecular sieves (MCM-41, S-1, and TS-1) were obtained from the in situ generated nickel phyllosilicate as well. It seems that the strong interaction between Ni and Si species in nickel phyllosilicate precursor played a decisive role in the formation of highly dispersed and (2 0 1) plane-exposed Ni 2 P catalysts. [ABSTRACT FROM AUTHOR]

A promising hydrogen evolution reaction performance is achieved in this work by Ni 2 P nanoparticles supported on Nitrogen, Sulphur co-doped reduced graphene oxide (N ,S-rGO) synthesized via hydrothermal method. The enhanced electrochemical activity of the electrocatalyst can be attributed to the presence of more defect sites in the graphitic carbon as well as the synergistic effect between both N and S co-doped reduced graphene oxide. Ni 2 P–N, S-rGO showed the comparative intensity ratio I D /I G value of 1.96, which is higher compared to other carbon materials. It shows that the defect was increased when nitrogen and sulphur co-doping occurs on reduced graphene oxide sheets which in turn leads to an increase in both active doping sites and improve conductivity. Ni 2 P incorporated with N, S-rGO was found to be the best for attaining a current density of 10 mA/cm2 at an overpotential of 179 mV in 0.5 M H 2 SO 4. As well, the Tafel slope of 71 mV/dec confirms that the Ni 2 P incorporated with N, S-rGO proceeds through the Volmer-Heyrovsky mechanism. [Display omitted] [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]

[Display omitted] Nickel-based transition metal phosphides have been widely flourishing as oxygen evolution reaction (OER) electrocatalysts. In this study, a new catalyst Ni 2 P/Mn 2 O 3 nanofibers with the advantages of ultra-high electrochemical active area were successfully synthesized. We explored effective strategies that are constructing one-dimensional nanostructures and composite oxides to promote the electrocatalytic performance of transition metal phosphides. The Ni 2 P/Mn 2 O 3 nanofibers only require a low overpotential of 280 mV to deliver a current density of 10 mA cm−2 in 1 M KOH for oxygen production. As a result, it is worthily mentioned that the activity of Ni 2 P/Mn 2 O 3 nanofibers is virtually unchanged after 2000 cycles of voltammetry measurements with a stable nanostructure. This research provides a feasible solution for the design and realization of nanostructured electrocatalysts for the enhancing performance of the OER process. [ABSTRACT FROM AUTHOR]

In order to assess their potential use as contact layers for Si photonics devices, Ni2P thin films were developed on a 300 mm platform. The Ni2P layers, obtained by magnetron sputtering of a Ni2P target, were stable and reproducible. The films were mainly composed of the hexagonal Ni2P phase with small amount of Ni12P5 impurities. The film density was 6.9 g/cm3 with a ratio of 62 at.% of Ni and 38 at.% of P. We implemented and integrated these Ni2P films on III-V structures to study their electrical properties on n-InP and p-InGaAs (i.e., n-doped and p-doped III-V/Si hybrid laser contact layers). The results obtained on p-InGaAs did not meet the requirements in terms of contact resistivity. On the other hand, due to its high thermal stability and low contact resistivities, Ni2P metallization exhibited the best results among the Ni-based metallizations studied for contacting n-InP layers, namely Ni, NiPt and Ni2P.

Oxygen evolution reaction (OER) as the foremost stumbling block to generate cost-effective clean fuels has received extensive attention in recent years. But, it still maintains the challenge to manipulate the geometric and electronic structure during single reaction process under the same conditions. Herein, we report a simple self-template strategy to generate honeycomb-like Ni2P/N,P–C hybrids with preferred electronic architecture. Experiments coupled with theoretical results revealed that the synthesized catalyst has two characteristics: firstly, the unique honeycomb-like morphology not only enables the fully utilization of catalytic active sites but also optimizes the mass/electron transportation pathway, which favor the diffusion of electrolyte to accessible active sites. Secondly, N,P–C substrate, on the one hand, largely contributes the electronic distribution near Fermi level (EF) thus boosting its electrical conductivity. On the other hand, the support effect result in the upshift of d-band center and electropositivity of Ni sites, which attenuates the energy barrier for the adsorption of OH− and the formation of ∗OOH. In consequence, the optimized Ni2P/N,P–C catalysts feature high electrocatalytic activity towards OER (a low overpotential of 252 mV to achieve 10 mA cm−2) and 10 h long-term stability, the outstanding performance is comparable to most of transition metal catalysts. This work gives a innovative tactics for contriving original OER electrocatalysts, inspirng deeper understanding of fabricating catalysts by combining theoretical simulation and experiment design.

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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.

[Display omitted] Urea electrolysis is a promising hydrogen generation and urea-rich wastewaters treatment technology, which requires the development of highly active electrocatalysts. In this study, porous hetero-structured nanosheet electrocatalyst (NiO/Ni 2 P/NF), composed of crystalline NiO and Ni 2 P, is prepared via the in-situ acid etching and gas-phase phosphating method, and the obtained NiO/Ni 2 P/NF material is applied as efficient urea oxidation and hydrogen evolution catalyst for the overall splitting of urea-containing wastewaters. An electrolyzer containing NiO/Ni 2 P/NF||NiO/Ni 2 P/NF electrode pair in an alkaline urea aqueous solution requires a potential of just 1.457 V to reach a current density of 10 mA cm−2, lower than that of 1.490 V needed for a Pt/C/NF||RuO 2 /NF electrolyzer to operate under the same current density. The study demonstrates the synergistic effect between NiO/Ni 2 P nanosheets as well as their uniform pore structure formed by the Kirkendall effect, resulting in enhanced electrocatalytic performance in hydrogen production by urea electrolysis. [ABSTRACT FROM AUTHOR]

• A simple method was reported for synthesis of MOFs-derived carbon-covered Ni 2 P. • Ni 2 P@C-3 catalysts showed best catalytic activity for vanillin conversion to MMP. • The acid sites played a significant role in the CTH of vanillin to MMP. The catalytic transfer hydrodeoxygenation (CTH) of lignin and its derivates to biofuels and fine chemicals was a promising technology for efficient utilization of biomass. Herein, a series of MOFs derived carbon-covered Ni 2 P@C-x catalysts were successfully fabricated via chemical vapor deposition for the CTH of lignin-derived vanillin to produce 2-methoxy-4-methylphenol (MMP). Ni 2 P@C-3 catalyst exhibited an excellent CTH performance, obtaining nearly 100 % conversion of vanillin and 95 % yield of MMP under the conditions of 180 °C, 3 h, and 0 MPa N 2 in an isopropanol environment. Based on characterization results, the high catalytic activity of Ni 2 P@C-3 catalyst was attributed to Niδ+ species owing to the electron transfer from Ni to P and the P-OH groups in Ni 2 P phase, which provided more Lewis acid sites and Brønsted acid sites. Moreover, the small particle size with high dispersion and surface carbon defects also promoted the CTH performance. This work could provide some useful insights for the hydrodeoxygenation of lignin and its derivatives in the future. [ABSTRACT FROM AUTHOR]

In situ obtained Ni 2 P-based catalysts were proposed for the selective conversion of terephthalic acid into the benzene-toluene-xylene fraction. The catalysts were characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy and NH 3 temperature-programmed desorption. The influence of reaction time, temperature and H 2 pressure on the conversion of terephthalic acid and benzene-toluene-xylene selectivity was studied. Direct deoxygenation and decarboxylation were found to be the main reaction pathways using in situ Ni 2 P catalysts. Selectivity for the benzene-toluene-xylene fraction reached up to 100 % (at full terephthalic acid conversion) under moderate reaction conditions. The reusability of the in situ Ni 2 P catalyst before and after regeneration was demonstrated. [Display omitted] • Ni 2 P catalyst formed in situ in the hydroprocessing of terephthalic acid. • Benzene-toluene-xylene fraction was produced with 100 % selectivity at 350 °C. • Niδ+ promotes the decarboxylation pathway. • P–OH are the active sites in the direct deoxygenation. • In situ Ni 2 P can be regenerated and reused in the terephthalic acid processing. [ABSTRACT FROM AUTHOR]

High entropy alloys (HEAs) have emerged as a promising electrocatalyst, owing to its high entropy configuration, rich defects, and strong synergism. In this study, a solvothermal method was used to prepare amorphous transition metal-based HEA. Subsequently, HEA/Ni 2 P heterostructures were formed on the surface of HEA through an electrodeposition-assisted pyrolysis strategy. The resulting self-supporting HEA/Ni 2 P heterojunction electrode exhibited a low overpotential of 255 mV at 10 mA·cm−2, a small Tafel slope of 56.86 mV·dec−1, and a long-term durability of 24 h in 1.0 M KOH. The formation of the heterojunction could adjust the electronic structure of the amorphous HEA, improve the electron transfer between HEA and Ni 2 P, thus enhance the OER activity of the composite. This study not only presents a novel strategy for constructing electrocatalysts based on HEA but also demonstrates the significant application of HEA in the field of electrocatalysis. [Display omitted] • Amorphous/crystalline heterostructure (HEA/Ni 2 P) was prepared on a NF substrate. • The OER activity of HEA/Ni 2 P in 1.0 M KOH achieved 255 mV@10 mA·cm−2. • HEA adjusted the electronic structure and improved the electron transfer. • The construction of heterostructure enhanced the catalytic efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon-coated Ni 2 P@C/FLRC-TiO 2 catalysts with flower-like radial channels were prepared. • Open radial channels of FLRC-TiO 2 promote fast mass transfer and shorten reaction time. • The reaction rate constant k value of Ni 2 P@C/FLRC-TiO 2 -1 is 4.7 times that of Ni 2 P@C/TiO 2. • The Ni 2 P@C/FLRC-TiO 2 showed 100 % deoxidation products yield within 1.5 h. Efficient hydrodeoxygenation (HDO) catalysts are of great important for converting biomass to value-added chemicals and fuels. Herein, a novel strategy was proposed for preparing a highly dispersed carbon-encapsulated flower-like radial channels TiO 2 -supported catalysts (Ni 2 P@C/FLRC-TiO 2). The effect of P and pore structure of the TiO 2 support on the p-cresol HDO performance was investigated. An appropriate P content improves the HDO performance by increasing the acidity, while the open radial channels of Ni 2 P@C/FLRC-TiO 2 greatly reduces the reaction time and enhance the HDO activity by promoting rapid mass transfer and accessibility of active sites. The highly dispersed carbon-encapsulated Ni 2 P@C nanoparticles further improve the HDO activity and stability. Among the prepared catalysts, Ni 2 P@C/FLRC-TiO 2 -1 (initial NaH 2 PO 2 :Ni-MOF/FLRC-TiO 2 mass ratio = 1) exhibited the best HDO performance, yielding 100 % of the p -cresol deoxygenation products within 1.5 h under mild conditions. The excellent HDO performance originates from the synergy between FLRC-TiO 2 radial channels and the Ni 2 P@C nanoparticles. [ABSTRACT FROM AUTHOR]

Effect of phosphorus on the furfural HDO over nickel and nickel phosphide catalysts. [Display omitted] • Furfural HDO activity decreases in order: Ni 2 P ≈ MoP > Co 2 P > WP ≫ Cu 3 P > Fe 2 P. • More stable η2(C, O) adsorption on surfaces with increasing P/metal ratio. • More Brønsted acid sites with increasing P/metal ratio. • Furan-ring hydrogenation and ring opening suppressed with increasing P/metal content. • The carbonyl group conversion increased at higher P/metal ratio. The gas-phase hydrodeoxygenation (HDO) of furfural, a model compound for bio-based conversion, was investigated over transition metal phosphide catalysts. The HDO activity decreases in the order Ni 2 P ≈ MoP > Co 2 P ≈ WP ≫ Cu 3 P > Fe 2 P. Nickel phosphide phases (e.g., Ni 2 P, Ni 12 P 5 , Ni 3 P) are the most promising catalysts in the furfural HDO. Their selectivity to the gasoline additives 2-methylfuran and tetrahydro-2-methylfuran can be adjusted by varying the P/Ni ratio. The effect of P on catalyst properties as well as on the reaction mechanism of furfural HDO were investigated in depth for the first time. An increase of the P stoichiometry weakens the furan-ring/catalyst interaction, which contributes to a lower ring-opening and ring-hydrogenation activity. On the other hand, an increasing P content does lead to a stronger carbonyl/catalyst interaction, i.e., to a stronger η2(C, O) adsorption configuration, which weakens the C1 O1 bond (Scheme 1) in the carbonyl group and enhances the carbonyl conversion. Phosphorus species can also act as Brønsted acid sites promoting C1 O1 (Scheme 1) hydrogenolysis of furfuryl alcohol, hence contributing to higher production of 2-methylfuran. [ABSTRACT FROM AUTHOR]

Abstract 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 .

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 $$\sqrt 7 \times \sqrt 7 {\ }R19.1^\circ $$ structure, but above 673 K, other complex structures were created. These structures seemed to correlate with each other and we reinterpret a $$\sqrt 7 \times \sqrt 7 {\ }R19.1^\circ $$ structure of P adsorbed on Ni(111) based on the similarities of these surface structures. The new rectangular structure for the $$\sqrt 7 \times \sqrt 7 {\ }19.1^\circ $$ is discussed in relation to the Ni2P local structure.

[Display omitted] • The kinetics of phenol hydrodeoxygenation over Ni 2 P, Ni 12 P 5 and Ni 3 P was studied. • The metallicity of nickel phosphides increased from Ni 2 P, Ni 12 P 5 to Ni 3 P. • The acid amounts of nickel phosphides decreased with increasing Ni/P molar ratio. • Dehydration of cyclohexanol was rate-determining step in phenol hydrodeoxygenation. • Ni 3 P exhibited the highest hydrogenation performance, whereas Ni 2 P for dehydration. Three representative nickel phosphides (Ni 2 P, Ni 12 P 5 and Ni 3 P) were prepared and characterized comparatively by means of XRD, N 2 adsorption-desorption, ICP, TEM, XPS and NH 3 -TPD. It is shown that the binding energy ascribed to Ni δ + in nickel phosphide decreased, whereas that of P δ− increased, as the Ni/P molar ratio increased from 2 (Ni 2 P) to 2.4 (Ni 12 P 5) and to 3 (Ni 3 P). It is indicated that the slight transfer of electron density from Ni to P atoms decreased from Ni 2 P, Ni 12 P 5 to Ni 3 P. NH 3 -TPD measurements revealed that the total acid amounts of the nickel phosphides decreased with increasing Ni/P molar ratio. Their catalytic performance in hydrodeoxygenation (HDO) were investigated using phenol in decalin (1.0 wt%) as the feed. It is found that phenol was readily hydrogenated to yield cyclohexanol over all the three unsupported nickel phosphides at low temperatures and the subsequent HDO of cyclohexanol was rate-determining. As a result, the overall kinetics of phenol HDO were investigated by measuring the rates of phenol HDO and cyclohexanol HDO. The activation energy for phenol hydrogenation decreased in the order Ni 2 P > Ni 12 P 5 > Ni 3 P, whereas that for cyclohexanol dehydration increased. [ABSTRACT FROM AUTHOR]

Inadequate photogenerated carriers' separation is deemed to be the major obstacles for improving photocatalytic H 2 evolution. Here, we designed distinctive Ni 2 P/porous g-C 3 N 4 /Cd 0.5 Zn 0.5 Se-diethylenetriamine (Ni 2 P/pg-C 3 N 4 /Cd 0.5 Zn 0.5 Se-D) nanojunction via an in-situ solvothermal synthesis. The cooperative effect of Cd 0.5 Zn 0.5 Se-D and Ni 2 P can extend the visible light absorption for pg-C 3 N 4. As a result, the ternary Ni 2 P/pg-C 3 N 4 /Cd 0.5 Zn 0.5 Se-D composite exhibits high-performance H 2 evolution rate of 12627 μmol g−1 h−1 using solar light, being almost 105.23 and 2.59 folds higher than those observed over Ni 2 P/pg-C 3 N 4 and pg-C 3 N 4 /Cd 0.5 Zn 0.5 Se-D composite, severally. The possible mechanism is assumed that the formation of the novel Ni 2 P modified step-scheme (S-scheme) pg-C 3 N 4 /Cd 0.5 Zn 0.5 Se-D heterojunction which manipulated highly efficient spatial separation and directional migration of photocarriers. Moreover, DFT calculations have been performed to uncover the process of the charge transport. This work concentrates on the profound part of noble-metal-free decorated S-scheme photocatalytic system in water splitting. [ABSTRACT FROM AUTHOR]

A growing trend in electrocatalysis is to explore interfacial interactions and surface intermediate adsorption in highly efficient bimetallic phosphide catalysts for developing efficient oxygen evolution reactions (OER). In this work, Ni 2 P and Co 2 P nanoparticles (NPs) were distributed on P-modified NiMoO 4 nanorods prepared by the hydrothermal procedure, which exhibited high catalytic activity and outstanding durability for the OER. By regulating the high interfacial contact between Ni 2 P, Co 2 P, and P-NiMoO 4 , the Ni 2 P and Co 2 P NPs reduced the electron density, thus optimizing the OER. Compared to the NiMoO 4 NRs, the P-NiMoO 4 @Ni 2 P/Co 2 P electrocatalyst showed remarkable activity towards the OER owing to the strong electron interaction and synergistic effect among the three components. Consequently, the P-NiMoO 4 @Ni 2 P/Co 2 P electrode yielded significant OER activity, with an overpotential of 260 mV, a Tafel slope of 41 mV/dec, and 92.9% Faradaic efficiency. Furthermore, the P-NiMoO 4 @Ni 2 P/Co 2 P electrocatalyst demonstrated excellent stability (up to 50 h) for the OER, which was higher than those of the NiMoO 4 -based catalysts reported in the literature. Several factors contribute to the excellent OER activity, including electron transfer between Ni 2 P, Co 2 P, and P-NiMoO 4 , and the abundant active sites generated from their interfacial interactions. Therefore, this study presents a novel approach for developing highly efficient ternary electrocatalysts for the long-term electrocatalytic evolution of oxygen. [Display omitted] • Synthesizing P-NiMoO 4 @Ni 2 P/Co 2 P by hydrothermal and phosphorization methods. • Ni 2 P/Co 2 P plays a critical role in enhancing the charge/mass transport process. • Strong electron interaction and synergistic effect of Ni 2 P/Co 2 P to improved OER activity. • P-NiMoO 4 @Ni 2 P/Co 2 P exhibits the best OER activity with low overpotential of 260 mV. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni 2 P/BP is formed by doping Ni onto the surface of black phosphorus (BP) by a one-pot method successfully. • The as prepared Ni 2 P/BP shows a better ambient stability and more efficient interfacial charge separation than that of BP under NIR light irradiation. • The Ni 2 P/BP can activate oxygen to generate singlet oxygen through Russell Mechanism for water remediation and disinfection under NIR irradiation. Black phosphorus (BP) shows great potential applications in photoelectric conversion and photocatalysis, but its applications are limited by its disadvantages such as poor ambient stability and rapid carrier recombination under photoirradiation. In this work, it was surprisingly found that the in-situ generation of Ni 2 P onto the surface of BP leaded to a significant improvement in both ambient stability and photocatalytic singlet oxygen (1O 2) generation under NIR irradiation. Because of the transfer of electrons from Ni to BP via Ni-P bonds, the Ni 2 P/BP showed better charge separation efficiency and ambient stability in NIR photoelectric conversion. Moreover, the Ni 2 P/BP was able to generate 1O 2 for NIR photocatalysis through Russell Mechanism. Meanwhile, norfloxacin and E. coli could also be removed by Ni 2 P/BP under NIR irradiation, which further shows the ability to generate 1O 2 for practical utilization. This work provides a novel insight into the passivation of BP by hetero-atoms doping and a new strategy for green NIR photocatalytic water remediation. [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 main prerequisite for designing electrocatalysts with favorable performance is to examine the links between electronic structural features and catalytic activity. In this work, Ni 2 P as a model electrocatalyst and one of the most potent catalysts for hydrogen evolution reaction (HER) was utilized to develop various Ni 2 P and carbon-based (graphene and N-doped graphene) heterostructures. The characteristics of such structures (Ni 2 P, graphene, N-doped graphene, Ni 2 P/graphene, and Ni 2 P/N-doped graphene), including binding energies, the projected density of states (PDOS), band structure, charge density difference, charge transfer, Hirshfeld charge analysis, and minimum-energy path (MEP) towards HER were calculated and analyzed by density functional theory (DFT) approach. The coupling energy values of hybrid systems were correlated with the magnitude of charge transfer. The main factors driving a promising water-splitting reaction were explained by the data of PDOS, band structures, and charge analysis, including the inherent electronegativity of the N species alongside shifting the Fermi level toward the conductive band. It was also shown that a significant drop occurs in the HER energy barrier on Ni 2 P/graphene compared to the pristine Ni 2 P due to N doping on the graphene layer in the Ni 2 P/N-doped graphene heterostructure., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

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]

Abstract 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.

• Desulfurization networks of 2-phenylcyclohexanethiol (2-PCHT) under H 2 and Ar. • β-Elimination dominated the hydrodesulfurization of 2-PCHT over Ni 2 P. • MoP and WP showed much higher hydrogenolysis activity than Ni 2 P. • Dehydrogenation of 2-PCHT occurred over the phosphide catalysts. • The phosphosulfide phases were formed both under H 2 and Ar. The desulfurization of 2-phenylcyclohexanethiol (2-PCHT) was studied over Ni 2 P, MoP, and WP under 4.0 MPa H 2 or Ar at 240 °C. The hydrodesulfurization of 2-PCHT proceeded through three parallel pathways: β-elimination, hydrogenolysis, and dehydrogenation. Under Ar, the parallel pathways were β-elimination, hydrogenolysis or homolytic C–S bond cleavage, and dehydrogenation. MoP and WP were more active than Ni 2 P. β-Elimination dominated the hydrodesulfurization of 2-PCHT over Ni 2 P, while hydrogenolysis was as fast as β-elimination over MoP and WP. Under Ar, β-elimination and dehydrogenation pathways were about equal over Ni 2 P, whereas β-elimination was the major pathway over MoP and WP. The inhibiting effects of piperidine depended on the reaction and catalyst. Phosphosulfide phases were formed under both H 2 and Ar, but the sulfidation behavior of Ni 2 P was different from that of MoP and WP. Ni 2 P was more difficult to sulfide than MoP and WP under H 2. [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]

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]

[Display omitted] • Ni-2.5P/Al 2 O 3 catalyst offered remarkable phenanthrene hydrogenation activity and stability. • Ni-2.5P/Al 2 O 3 catalyst possessed suitable electron-deficient state and Ni active sites. • Phosphate deposition induced an appropriate Ni electron-deficient state. • Balance between electron-deficient state and the exposed Ni active sites was tuned by varying P/Ni molar ratios. Ni 2 P/Al 2 O 3 catalysts with phosphate deposition were synthesized by a hypophosphite decomposition method. Benefiting from its spherical structure and special electronic properties derived from the deposited phosphate on the catalyst surface, the Ni-2.5P/Al 2 O 3 catalyst offered remarkable activity and stability towards phenanthrene (PHE) hydrogenation, featuring a high turnover frequency of 44.64 × 10-3 s−1. Extensive characterizations revealed that the control of P/Ni molar ratio could change the phosphorus migration pathway and affect the amount of the generated phosphate deposition and then the exposed active sites of Ni 2 P. Density functional theory computations indicated that the deposited phosphate could induce electron transfer from Ni to phosphate, and a certain amount of phosphate deposition can endow Ni with an appropriate electron-deficient state, which can improve the PHE adsorption and result in a facile complete PHE hydrogenation. [ABSTRACT FROM AUTHOR]

Transition-metal phosphides and phosphosulfides constitute a class of versatile and promising catalysts in the field of enery production. The preparation of nanostructured phosphides and phosphosulfides is chanllenging because the thermal reduction of phosphate precursors requires high temperatures. In the present work, nanostructured nickel phosphosulfide catalysts composed of Ni 2 P particles surrounded by a distinct sulfur-containing layer were prepared by reduction of mixtures of Na 4 P 2 S 6 and NiCl 2 in H 2 plasma. The minimum P/Ni ratio needed for the formation of nickel phosphosulfide was between 4/7 and 2/3, and the input voltage of the plasma generator (V in) should be higher than 40 V. The control of the particle sizes of the nickel phosphosulfide catalysts was realized by simply regulating V in. Another minor factor affecting the particle size was H 2 flow rate. The actual precursor for the formation of nickel phosphosulfide can be Ni 2 P 2 S 6 , which underwent fast reduction in H 2 plasma to yield NiS. In the hydrodesulfurization of dibenzothiophene, the nanostructured nickel phosphosulfide catalyst exhibited higher activity and hydrogenation pathway (HYD) selectivity than the one with large particle size. The optimal P/Ni ratio of the nickel phosphosulfide catalysts was found to be 4/5, and the HYD pathway was more favored by the increase in the P/Ni ratio than the direct desulfurization pathway. [Display omitted] • Mixtures of Na 4 P 2 S 6 and NiCl 2 were used as catalyst precursors. • Preparation of nickel phosphosulfide (NiPS) by H 2 plasma reduction of the mixtures. • The control of the particle size of NiPS by regulating the input voltage. • The minimum P/Ni ratio of the mixture for the formation of NiPS was 2/3. • Large NiPS particles showed lower hydrodesulfurization activity than nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract 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.

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.

Graphical abstract Highlights • Ni 2 P/Ga-SiO 2 shows a higher DDS selectivity than Ni 2 P/SiO 2 in the HDS of 4,6-DMDBT. • The Ga addition induces electron-deficient Ni 2 P favoring σ-bonding with 4,6-DMDBT. • The high DDS selectivity of Ni 2 P/Ga-SiO 2 allows less H 2 consumption in the HDS. Abstract Ni 2 P catalysts supported on SiO 2 and Ga-SiO 2 were prepared by incipient wetness impregnation technique, and the effect of the electronic properties of Ni 2 P on hydrodesulfurization (HDS) performance was studied. X-ray diffraction (XRD), X-ray absorption near edge structure (XANES), and in situ FT-IR with CO adsorption studies were used to examine structural and electronic properties of the supported Ni 2 P catalysts. The catalytic activity in hydrodesulfurization (HDS) was measured at 3.0 MPa and at three different temperatures of 613, 628, and 643 K in a three-phase fixed bed reactor using a model feed containing 500 ppm S as 4,6-DMDBT, 6000 ppm S as DMDS, 100 ppm N as quinoline, 1 wt% tetralin, and 0.5 wt% n-nonane in n-tridecane balance. In both cases, the HDS conversion was very high over 90%. For the product distributions, the Ni 2 P/SiO 2 maintained a low direct desulfurization (DDS) selectivity at 26.5%, while the Ni 2 P/Ga-SiO 2 exhibited higher DDS selectivity of 32.1% at 643 K. The Ni K-edge XANES and CO-adsorbed FT-IR analysis confirmed the electron enriched property of Ni 2 P on SiO 2 , but with the electron deficiency of Ni 2 P phase supported on Ga-SiO 2 support. These results thus suggest that the electron deficient Ni 2 P favors σ-bonding with S compounds to promote direct desulfurization of 4.6-DMDBT. [ABSTRACT FROM AUTHOR]

Graphical abstract The reasonable design and controllable preparation of MoO 3 @Ni 2 P make it exhibit much high photocatalytic activities for H 2 evolution with about 39.8 and 15.8 times compared to the pure MoO 3 and Ni 2 P. The investigation indicates that the assembly of Ni 2 P nanoparticles and MoO 3 can provide more active sites and accelerate the transfer of electrons. Abstract Effectiveness and stability of photocatalyst are of importance not only for improving H 2 evolution, but also for the realization of enhanced semiconductors property in practical applications. In this study, a novel MoO 3 @Ni 2 P hybrid nanostructure is successfully prepared by a two step strategy of one-pot pyrolysis followed by calcination method. The reasonable design and controllable preparation of MoO 3 @Ni 2 P make it exhibit much high photocatalytic activities for H 2 evolution with about 39.8 and 15.8 times compared to the pure MoO 3 and Ni 2 P. This prominently increased effect is certified by results of various characterization such as SEM, TEM, XRD, XPS, BET, FT-IR, UV–vis DRS, transient photocurrent, steady-state fluorescence, transient-state fluorescence and Mott-Schottky studies etc. The investigation indicates that the assembly of Ni 2 P nanoparticles and MoO 3 can provide more active sites and accelerate the transfer of electrons. Moreover, the possible mechanism of photocatalytic H 2 generation is proposed. [ABSTRACT FROM AUTHOR]

Abstract The catalytic performances of various nickel phosphide catalysts (NiP) supported on ZrO 2 synthesized with different P/Ni molar ratios (0.8, 2 and 3) were investigated in hydrodeoxygenation (HDO) of m-cresol at 340 °C under 4 MPa. The solid sample with the highest P/Ni ratio (NiP-3/ZrO 2) presented the best catalytic performances in terms of activity, which were attributed to the presence of the pure Ni 2 P phase, the other samples containing either a mixture of Ni 2 P and Ni 12 P 5 (NiP-2/ZrO 2) or Ni 12 P 5 (NiP-0.8/ZrO 2) alone were less active. The use of ZrO 2 as support required a large excess of P to obtain Ni 2 P as active phase. Graphical abstract Unlabelled Image Highlights • Ni 2 P phase was more active than the Ni 12 P 5 phase in HDO of m-cresol. • A large excess of P was required to obtain Ni 2 P when ZrO 2 is used as support. • Methylcyclohexane was always the main deoxygenated product. • The distribution product was not affected by the nature of phosphide phase. [ABSTRACT FROM AUTHOR]

Abstract The development of a highly-efficient co-catalyst using earth-abundant elements is important to improve photocatalytic H 2 evolution. Herein, we prepared Ni 2 P-Zn 0.5 Cd 0.5 S (NPZCS) porous composites suitable for photocatalytic H 2 evolution under visible light irradiation. The in-situ synthesis and loading of Ni 2 P nanoparticles onto the porous structure of ZCS was achieved in one-step by a hydrothermal method without the addition of any surfactants or templates. It was revealed that porous ZCS exhibited advanced photocatalytic performance. Furthermore, the optimized NPZCS showed remarkably enhanced photocatalytic activity for H 2 evolution under visible light irradiation. An optimal H 2 evolution rate of 912.57 μmol•h−1 was observed over NPZCS loaded with 0.125% Ni 2 P, with a calculated apparent quantum efficiency of 37.5% at 420 nm. Loading of the Ni 2 P co-catalyst provided active reaction sites, boosted the efficiency of photoinduced electron-hole pair separation and extended the lifetime of photoinduced charge, resulting in enhanced photocatalytic H 2 evolution efficiency under visible light irradiation. Graphical abstract Image 1 Highlights • Ni 2 P-Zn 0.5 Cd 0.5 S photocatalyst was synthesized by a facile hydrothermal method. • Ni 2 P as a cocatalyst separates the electron-hole pairs efficiently. • Ni 2 P-Zn 0.5 Cd 0.5 S shows improved photoactivity in H 2 evolution via water splitting. [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.

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]

Non-noble-metallic Ni 2 P modified BiOBr with oxygen vacancy (O V) was synthesized by solvothermal method to construct novel O V -BiOBr/Ni 2 P nanoheterojunction. Compared with O V -BiOBr, the photoelectrochemical hydrogen evolution of O V -BiOBr/Ni 2 P was significantly improved. O V -BiOBr/Ni 2 P-2% showed the best hydrogen evolution rate of 455.34 μmol · cm−2 · h−1 without sacrificial agent, which was 5.94 times that of O V -BiOBr and 12.88 times that of pristine BiOBr. It was found that an appropriate amount of Ni 2 P loading enabled the closely contacted O V -BiOBr/Ni 2 P to have an optimal O V concentration, which realized the rapid electron-hole separation, simultaneously, the successful loading of Ni 2 P can effectively enhance the light absorption capacity. The formation of Bi-O-P chemical bond and nanoheterojunctions jointly promote electron transfer and inhibit carrier recombination. Density functional theory (DFT) calculations find that the hydrogen adsorption free energy of O V -BiOBr/Ni 2 P heterojunction is the lowest in this system. This study will provide some guidance for efficient photoelectrochemical hydrogen evolution without sacrificial agent. [Display omitted] • Concentration of oxygen vacancy can be regulated by Ni 2 P content in O V -BiOBr/Ni 2 P. • Bi-O-P chemical bond and O V -BiOBr/Ni 2 P heterojunction promote electron transfer. • O V -BiOBr/Ni 2 P displays boosting PEC hydrogen evolution without sacrificial agent. [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.