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Due to the synergistic effect of the rapid transfer of photo-generated electrons and enrichment of reactive active sites, reasonably assembling dual cocatalysts with semiconductor is considered as an excellent method to enhance the photocatalytic properties of semiconductors. Herein, earth-abundant Co 9 S 8 and Ni 2 P dual cocatalysts modified-ZnIn 2 S 4 (ZIS/CS/NP) composite photocatalyst has been constructed by the low-temperature solvothermal and in-situ photodeposition methods. A series of characterizations indicate the hollow structure of Co 9 S 8 can reduce the charge transfer distance and enhance the migration of photo-generated electrons, while Ni 2 P acts as an electron collector and provides sufficient active sites for H 2 release in this dual cocatalysts system. Because of the synergistic effect of dual cocatalysts, ZIS/CS/NP composites exhibit superior activity in the photocatalytic H 2 production compared to blank ZIS, ZIS/CS and ZIS/NP. Notably, the optimal photocatalytic H 2 production rate of ZIS/CS/NP reaches 6823.64 μmol g−1 h−1, which is approximately 86 times higher that of blank ZIS. This work is expected to provide useful reference for the construction of high-performance dual-cocatalyst modified semiconductor composite for photocatalytic H 2 evolution. The ZnIn 2 S 4 /Co 9 S 8 /Ni 2 P composite photocatalyst was synthesized through low-temperature solvothermal and in-situ photodeposition methods to achieve efficient photocatalytic hydrogen evolution. In this dual cocatalysts system, the hollow structure of Co 9 S 8 can reduce the charge transfer distance and enhance the migration of photo-generated electrons of ZnIn 2 S 4 , while Ni 2 P acts as an electron collector and provides sufficient active sites for H 2 release. [Display omitted] • ZnIn 2 S 4 /Co 9 S 8 /Ni 2 P ternary composite has been synthesized. • ZnIn 2 S 4 /Co 9 S 8 /Ni 2 P exhibits superior performance in photocatalytic H 2 evolution. • Co 9 S 8 and Ni 2 P dual cocatalysts are rationally utilized. • Dual cocatalysts synergistically enhance transfer of electrons and enrichment of active sites. [ABSTRACT FROM AUTHOR]

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]

A series of physical mixtures of Na4P2S6 and NiCl2 (P‐NiPS(x), where x represents the P/Ni molar ratio) were employed for the preparation of Ni2P. For comparison, a sulfur‐containing Ni2P catalyst (Ni2P‐S) and a sulfur‐free Ni2P catalyst (Ni2P‐TPR) were prepared by reduction of Ni2P2S6 and a nickel phosphate precursor, respectively. The reduction of the P‐NiPS(x) precursors with P/Ni ratios above 2/3 yielded Ni2P catalysts with a distinct nickel phosphosulfide layer (NiPS(x)), and the Ni2P phase started to form at ca. 200 °C. The reduction of Ni2P2S6 to Ni2P most likely follows a disproportionation mechanism. The P3+ species in Ni2P2S6 disproportionate to PH3 and P5+ during the reduction, and PH3 further reacts with nickel and sulfur species to form Ni2P and the surface nickel phosphosulfide layer. The sulfur atoms in the nickel phosphosulfide phase were in the form of S2−. The introduction of sulfur to Ni2P favored the hydrogenation pathway of the hydrodesulfurization (HDS) of dibenzothiophene (DBT), but hardly affected the direct desulfurization (DDS) pathway and inhibited the hydrogenation of biphenyl. The DDS pathway rate constants of DBT HDS over the Ni2P‐TPR and NiPS(x) catalysts were observed to increase linearly with the increase in their surface Ni atomic concentrations. [ABSTRACT FROM AUTHOR]

To enhance the activity of photocatalysts, it is crucial to use non-noble metal as a cocatalyst instead of noble metal in the arena of photocatalysis. In this study, to boost the photocatalytic hydrogen activity of pristine Zn 2 In 2 S 5 , XNi 2 P/ZIS 5 composite photocatalysts were prepared using noble-metal-free Ni 2 P as cocatalyst. Before photocatalytic hydrogen production experiments, the physicochemical properties of the synthesized materials were systematically characterized by advanced characterization methods. The experiment results demonstrate that the load of Ni 2 P cocatalyst can noticeably enhances the photocatalytic performance of Zn 2 In 2 S 5 and the photocatalytic hydrogen generation activities are observably influenced by the mass ratio of Ni 2 P to Zn 2 In 2 S 5. Among XNi 2 P/ZIS 5 , the 10Ni 2 P/ZIS 5 sample presents the optimal hydrogen production rate of 17.74 mmol g−1 h−1, which is 7.58 times as high as that of pristine Zn 2 In 2 S 5. The increased photocatalytic hydrogen evolution activity could be attributed to the introduction of noble-metal-free cocatalyst Ni 2 P, which serves as an electronic collector and reduction sites remarkably facilitates the separation and migration of photoexcited electrons of Zn 2 In 2 S 5. Meanwhile, the rate of reactions is significantly accelerated. • XNi 2 P/Zn 2 InS 5 composite photocatalysts were prepared by using noble-metal-free Ni 2 P as cocatalyst. • XNi 2 P/Zn 2 InS 5 composite photocatalysts demonstrate excellent H 2 evolution performance. • Ni 2 P facilitates the separation and migration of photoexcited electrons of Zn 2 In 2 S 5 and accelerates the rate of reactions. [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]

Transition metal phosphides (TMPs) are ideal candidates to replace precious cocatalysts for photocatalytic hydrogen evolution reaction (HER). Understanding the structure-activity relationships between TMPs and the host photocatalysts is an important criterion for the development of highly active TMPs for HER. In this work, the relations were explored with Ni 2 P and g-C 3 N 4 as prototypes. Ni 2 P with a clear composition and structure was prepared first by a mild solvothermal method and was then loaded on g-C 3 N 4 with an exact content through a ball milling process. The effects of the modification of Ni 2 P on g-C 3 N 4 structure, absorption, texture, HER activity, and photo-electrochemical properties were investigated. The results demonstrated that the crystal structure and the texture of g-C 3 N 4 are less impacted by the decoration of Ni 2 P, but the HER activity can be substantially improved. g-C 3 N 4 modified with 3% Ni 2 P showed the highest HER performance and it is ca. 9 times higher than the pristine g-C 3 N 4 even Ni 2 P was loaded just by a simple ball milling process. Ni 2 P played a dual role as trapping sites to capture photoinduced electrons and the reactive centers to trigger the evolution of hydrogen for its high work function and the low HER overpotential. This work reveals some reliable structure-activity relationships between Ni 2 P and g-C 3 N 4 and offers a simple approach to synthesize highly efficient Ni 2 P and its loading on host photocatalyst for enhanced HER. [Display omitted] • New phosphidation process was developed to fabricate highly crystallized Ni 2 P. • Ball-milling g-C 3 N 4 with Ni 2 P could boost the photocatalytic HER activity. • The structure-activity relationships between Ni 2 P and g-C 3 N 4 was explored. • Ni 2 P played a dual role as e−-trapping centers and reactive sites to trigger HER. [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]

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]

Defect and interface engineering has been established as efficient methods for altering the electrical structure and improving the activity of electrocatalysts. Here, a rational design architecture consisting of Ni 2 P nanoparticles embedded in P-doped carbonized wood fibers (Ni 2 P/PCWF) is synthesized by simultaneous carbonization and phosphorization. A synergistic enhancement effect between electronic structure manipulation and interface regulation is observed in Ni 2 P/PCWF during the urea oxidation reaction (UOR). First, the P doping of carbon can optimize the electronic structure of Ni 2 P/PCWF. Second, the charge transport process is aided by the Ni 2 P nanoparticles embedded in the PCWF. Lastly, electron transfer can be accelerated by the in-situ formed heterogeneous interface between metal phosphides and metal hydroxides (hydroxyl oxides). Due to the synergy of the structural and electrical modulation, Ni 2 P/PCWF exhibits remarkable electrocatalytic properties toward the UOR under alkaline conditions. It only requires 1.34 V (vs. RHE) to achieve a current density of 50 mA cm−2, and the increase in potential at 10 mA cm−2 for 70 h is insignificant (≈2.9%). This work supports the development of new strategies using sustainable, renewable wood fibers to develop excellent UOR catalysts for energy-saving H 2 generation. [Display omitted] • A simple simultaneous phosphorization and carbonization strategy is developed to synthesize Ni 2 P/PCWF. • P doping into the carbon matrix can induce additional defects in carbon. • Metal phosphides/metal hydroxide heterogeneous interface was in-situ formed during the UOR process. • Ni 2 P/PCWF exhibits outstanding electrocatalytic performance for UOR. [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]

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]

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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Integrating electrochemical upcycling of polyethylene-terephthalate (PET) and the hydrogen evolution reaction (HER) is an energy-saving approach for electrolytic hydrogen (H 2 ) production, along with the coproduction of formate. Herein, a novel and rapid strategy of cold plasma phosphating is employed to synthesize Co 2 P-Ni 2 P heterointerface decorated on carbon cloth (Co 2 P-Ni 2 P/CC) to catalyze H 2 generation and reform PET. Notably, the obtained Co 2 P-Ni 2 P/CC exhibits eminent ethylene glycol oxidation reaction (EGOR) and HER activities, effectuating low potentials of merely 1.300 and -0.112 V versus RHE at 100 mA cm -2 for the EGOR and HER, respectively, also attaining an ultralow cell bias of 1.300 V at 10 mA cm -2 for EG oxidation assisted-water splitting. DFT and characterization results validate that the as-formed built-in electric fields in the Co 2 P-Ni 2 P heterointerface can accelerate electrons transfer and deepen structural self-reconstruction, thereby boosting effectively water dissociation and ethylene glycol (EG) dehydrogenation. Impressively, coupling HER with PET-derived EG-to-formate in a flow-cell electrolyzer assembled with Co 2 P-Ni 2 P/CC pair achieves an intriguing formate Faradaic efficiency of 90.6% and an extraordinary stable operation of over 70 h at 100 mA cm -2 . The work exemplifies a facile and effective strategy for synthesizing metal phosphides electrocatalysts with extraordinary performance toward H 2 generation of water splitting and recycling of PET., (© 2024 Wiley‐VCH GmbH.)

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]

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]

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]

Reliable and sustainable energy storage systems are crucial for a renewable energy future. The ultrahigh theoretical specific capacity and energy density of lithium–sulfur batteries (LSBs) make them one of the most promising next-generation battery technologies. However, their large-scale applications are seriously limited by rapid capacity fading and poor Coulombic efficiency owing to the shuttling of lithium polysulfides (LiPSs). Herein, we investigate nickel phosphide (Ni 2 P) as an effective host material to realize high-performance LSBs based on first-principles density functional theory (DFT) calculations. Our calculated adsorption energies of the LiPSs species reveal that the Ni 2 P(0001) surface possesses moderate to high adsorption strength and the adsorption process is facilitated via charge transfer from the LiPSs to the interacting Ni 2 P(0001) surface atoms. Due to the strong interactions between Ni 2 P(0001) and LiPSs (Li 2 S x , x = 1, 2, 4, 6 and 8), we observe elongation of the intramolecular Li–S bonds in LiPSs upon their adsorption. The stronger adsorption of Li 2 S coupled with its spontaneous dissociation suggests a faster charging process could occur on the on Ni 2 P(0001) surface. These results demonstrate that Ni 2 P can provide effective anchoring sites for the soluble LiPSs, potentially having implications for the design of electrodes for practical LSBs. [Display omitted] • Accurate first-principles characterization of LiPSs adsorption geometries. • Description of active sites on Ni 2 P (0001) surface. • Elucidation of charge transfer dynamics and anchoring behavior. • Findings on LiPSs catalytic degradation mechanisms and redox kinetics. [ABSTRACT FROM AUTHOR]

• The as-prepared Ni 2 P has a single-crystal. • Ni 2 P shows a special uniform hollow spherical structure. • Crystal structure and morphology of Ni 2 P can be controlled by the surfactants. • The as-prepared Ni 2 P exhibits excellent adsorption activity. The single-crystal Ni 2 P hollow spheres have been synthesized via a solvothermal route in presence of mixed surfactant. It is showed that solvent played a significant role for the synthesis of Ni 2 P. Furthermore, the structure of hollow spheres would be obtained only using the mixtures of cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl benzene sulfonate (SDBS) which act as soft template rather than single CTAB or pure SDBS. Finally, it turned out that the single-crystal Ni 2 P hollow spheres exhibit excellent adsorption activity for malachite green (MG) organic dyes. [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]

• A novel CdLa 2 S 4 /Ni 2 P catalyst with excellent photocatalytic H 2 evolution was introduced. • Catalyst with 15 % Ni 2 P dosage exhibited maximum photocatalytic H 2 evolution rate as 1.143 mmolh-1g−1, which was 10 times higher than that of pure CdLa 2 S 4. • The heterojunction structure formed by Ni 2 P and CdLa 2 S 4 improved the separation efficiency of photogenerated electron-hole pairs, thus prompted the H 2 evolution ability and the catalyst stability. Metal sulfides, often exhibited excellent photocatalytic H 2 evolution ability, has attracted more and more attention, whereas their industry applications were limited due to the photocorrosion. Therefore, the inhibition of photocorrosion is the key issue to promote the industrialization of metal sulfide catalysts. In this work, CdLa 2 S 4 /Ni 2 P catalysts with satisfactory H 2 evolution property were designed and synthesized. Catalyst with 15 % Ni 2 P dosage exhibited maximum photocatalytic H 2 evolution rate as 1.143 mmolh-1g−1, which was 10 times higher than that of pure CdLa 2 S 4. Such high catalytic efficiency maintained after 5 photocatalytic cycles. According to the results of transient photocurrent and photoluminescence, the heterojunction structure formed by Ni 2 P and CdLa 2 S 4 improved the separation efficiency of photogenerated electron-hole pairs, thus prompted the H 2 evolution ability and the catalyst stability. Further EPR results confirmed the existence of heterojunctions in the catalyst and proposed a possible reaction mechanism. The results show that the CdLa 2 S 4 /Ni 2 P composite photocatalyst has good visible light response and photochemical stability, and has broad application prospects in solar driven photocatalytic decomposition of water to hydrogen production. [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]

Utilizing highly efficient and stable photocatalysts to remove residual organic pollutants in wastewater has been deemed to be a promising and green technique for environmental management. Herein, novel 2D Ni 2 P/Bi 12 O 17 Cl 2 composites have been prepared by a facile deposition-precipitation method, and the structure, morphology, optical, photo-electrochemical and photoluminescence properties were characterized particularly. Oxytetracycline (OTC), phenol and methyl orange (MO) were selected as target pollutants to evaluate the photocatalytic performance of the Ni 2 P/Bi 12 O 17 Cl 2. Under visible light illumination (λ > 420 nm), the Ni 2 P/Bi 12 O 17 Cl 2 photocatalyst possesses outstanding photocatalytic properties for the degradation of OTC, phenol and MO than those of Bi 12 O 17 Cl 2. The enhanced photocatalytic activity of the Ni 2 P/Bi 12 O 17 Cl 2 is attributed to Ni 2 P acting as photogenerated electrons trappers to reinforce photoinduced charges separation. Furthermore, the Ni 2 P/Bi 12 O 17 Cl 2 photocatalyst owns outstanding stability. This study might shed light on the enhanced photocatalytic capacities of bismuth oxyhalide by means of embellishing transition metal phosphides in environment remediation fields. [Display omitted] Novel Ni 2 P/Bi 12 O 17 Cl 2 exhibited outstanding photocatalytic properties for the degradation of oxytetracycline (OTC), phenol and methyl orange (MO) is attributed to Ni 2 P acting as photoinduced electrons trappers to reinforce photoinduced charges separation. [ABSTRACT FROM AUTHOR]

The electrochemical synthesis of hydrogen peroxide (H 2 O 2) via the 2-electron pathway of oxygen reduction reaction offers a green and on-site product. However, there remains an urgent need to develop cost-efficient electrocatalysts with H 2 O 2 productivity that meets practical industrial-scale requirements. In this study, yeast-derived carbon material loaded with multiple Ni active sites achieved electrochemical synthesis of H 2 O 2 at industrial current density. The precursor of heteroatom-doped carbon material was obtained through high-dispersed Ni(II) adsorption on yeast cells. By adjusting the pyrolysis temperature and Ni loading dosage, the carbon framework, pore structure, and Ni active sites within the obtained Ni/yeast were successfully regulated. Ni/yeast featured with highly active Ni single-atom sites, metallic Ni nanoparticles and Ni 2 P nanoparticles, enabling stable running for 10 h at 200 mA cm−2 in a flow cell. Ni/yeast exhibits remarkable H 2 O 2 Faradaic efficiency of 94.6 % and a yield of 35.3 mol g cat −1h−1. The abundant pore structure and multiple Ni active sites within Ni/yeast provide promising avenues for manipulating heteroatom-doped carbon materials in H 2 O 2 electrosynthesis. [ABSTRACT FROM AUTHOR]

Photocatalytic nitrogen fixation is of great significance for solving the energy crisis and healthy development of the environment. However, photocatalysts have problems such as low activity, poor stability and difficult recovery, which seriously limit their application. Herein, we in situ synthesized g-C 3 N 4 /Ni 2 P/Ni three-dimensional reticulated foam photocatalysts (CNNPF) with excellent photocatalytic nitrogen fixation performance under visible light by a two-step methane sulfonic acid-assisted carbon nitride loading-calcined phosphatisation method, using nickel foam as the carrier and raw material. The results showed that the CNNPF had a stable three-dimensional network structure, and g-C 3 N 4 was stably immobilized to the nickel foam skeleton with Ni 2 P. The best performance of CNNPF with ultrasonication for 2 h and phosphatisation for 1 h showed a high photocatalytic nitrogen fixation efficiency of up to 373 μmol·h−1·g−1, which was attributed to the Ni 2 P co-catalyst modification of g-C 3 N 4 that led to the improvement of photogenerated electron-hole pair separation efficiency. Meanwhile, the three-dimensional network structure is favorable to provide more active sites for N 2 adsorption and activation. In addition, the prepared material also has good stability and recyclability, and its nitrogen fixation efficiency was still maintained at 350 μmol·h−1·g−1 after five cycles. The present work provides a direction for the design of efficient and recyclable photocatalytic systems that show great potential in the field of economically sustainable nitrogen fixation. [Display omitted] • g-C 3 N 4 /Ni 2 P/Ni three-dimensional reticulated foam photocatalysts (CNNPF) were in situ synthesized. • CNNPF has excellent photocatalytic nitrogen fixation performance under visible light. • Ni 2 P modification of g-C 3 N 4 to improve photogenerated electron-hole pair separation efficiency. • CNNPF also has good stability and recyclability. [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]

The direct urea fuel cell (DUFC) is a low cost and competitive approach for contemporaneous urine or urea-contaminated wastewater treatment and electricity generation. However, the lack of efficient urea oxidation reaction (UOR) electrocatalysts and suitable electron acceptors remains a challenge for practical applications. Here, we developed a DUFC system using Ni 2 P@Ni foam as the anode and peroxymonosulfate (PMS) as the chemical oxidizers. The Ni 2 P@Ni foam anode showed a high oxidation activity for UOR with an onset potential of 0.30 V vs. Ag/AgCl and Tafel slope of 34.4 mV/dec. PMS with high theoretical potential improved the cell voltage to 1.43 V. A power density of DUFC up to 4.91 mW/cm2 was achieved using PMS at room temperature, which was approximately twice as high as using H 2 O 2 (2.38 mW/cm2). NiII/NiIII was the redox active species on the Ni 2 P anode in the DUFC process, and NiII was electrochemically oxidized to NiIII, which reverted to NiII by urea reduction. When real human urine was used as the fuel, a power density of 4.46 mW/cm2 can be achieved at room temperature. This DUFC with high cell performance showed potential application in urea wastewater treatment. [Display omitted] [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.

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]

[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]

Ni 2 P nanoparticles and CdS nanorods were grew together on a mesoporous g-C 3 N 4 through a facile in-situ solvothermal approach. Under visible light (λ > 400 nm), the as-prepared ternary PCN–CdS-5% Ni 2 P composite displays a high H 2 evolution rate with 2905.86 μmol g−1 h−1, which is about 14, 18 and 279 times that of PCN–CdS, PCN–Ni 2 P and PCN, respectively. The enhanced photocatalytic activity is mainly attributed to the improved separation efficiency of the photocarriers by the type II PCN–CdS heterojunction and the effective extraction of photogenerated electrons by Ni 2 P. Meanwhile, Ni 2 P acts as co-catalyst to provide the photocatalytic active site for hydrogen reduction. In addition, PCN–CdS-5% Ni 2 P composite exerts good stability in 12-h cycles. [Display omitted] • Mesoporous g-C 3 N 4 decorated together by Ni 2 P and CdS was successfully fabricated. • The as-prepared PCN–CdS-5% Ni 2 P exhibits the excellent H 2 evolution rate. • PCN-CdS heterojunction and Ni 2 P co-catalyst synergistically enhance the separation efficiency of photocarriers. [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]

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]