Phosphide Nanowire Arrays Research Articles

Constructing a Built-In Electric Field To Accelerate Water Dissociation for Efficient Alkaline Hydrogen Evolution.

The alkaline hydrogen evolution reaction (HER) is intricately linked to the water dissociation kinetics. The quest for new strategies to accelerate this step is a pivotal aspect of enhancing the HER performance. Herein, we designed and synthesized a heterogeneous nickel phosphide/cobalt phosphide nanowire array grown on nickel foam (Ni2P/CoP/NF) to form a p-n junction structure. The built-in electric field (BEF) in the p-n junction optimizes the binding ability of hydrogen and hydroxyl intermediates, efficiently promoting water dissociation for the alkaline HER. Consequently, Ni2P/CoP/NF exhibits a lower overpotential of 58 and 118 mV at 30 and 100 mA cm-2, respectively, and high stability over 40 h at 300 mA cm-2 for the HER in 1 M KOH. Computational calculations combined with experiment results testify that the BEF presence in the p-n junction of Ni2P/CoP/NF effectively promotes water dissociation, regulates intermediate adsorption/desorption, and boosts electron transport. This study presents a rational design approach for high-performance heterogeneous electrocatalysts.

Heterostructured bimetallic phosphide nanowire arrays with lattice-torsion interfaces for efficient overall water splitting

Designing cost-effective and high-efficiency electrocatalysts is critical to the water splitting performance during hydrogen generation. Herein, we have developed Fe2P-Co2P heterostructure nanowire arrays with excellent lattice torsions and grain boundaries for highly efficient water splitting. According to the microstructural investigations and theoretical calculations, the lattice torsion interface not only contributes to the exposure of more active sites but also effectively tunes the adsorption energy of hydrogen/oxygen intermediates via the accumulation of charge redistribution. As a result, the Fe2P-Co2P heterostructure nanowire array exhibits exceptional bifunctional catalytic activity with overpotentials of 65 and 198 mV at 10 mA cm−2 for hydrogen and oxygen evolution reactions, respectively. Moreover, the Fe2P-Co2P/NF-assembled electrolyzer can deliver 10 mA cm−2 at an ultralow voltage of 1.51 V while resulting in a high solar-to-hydrogen conversion efficiency of 19.8% in the solar-driven water electrolysis cell.

Accelerating the surface reconstruction of cobalt phosphide via dual-doping engineering for high-performance water electrolysis

Most transition metal compound electrocatalysts would undergo potential-dependence phase conversion to generate actual active phase of anodic water oxidation. However, the dependence of high potential in electrochemical self-reconstruction, as well as the sluggish dynamics of water oxidation reaction are the main obstacles to real catalytic origins exploration and large-scale hydrogen fuel production. Herein, for the first time, sulfur and nickel dual-doped cobalt phosphide nanowire arrays (CoP3NiS NAs) are rationally designed as pre-catalysts, in which the S anions accelerate the surface reconstruction of the CoP3 while the Ni cations enhance the activity and selectivity of oxygen evolution reaction (OER). The converted products (CoP3NiS-R NAs) exhibit the overpotential of only 260 mV at 100 mA cm−2 for OER, much superior to the CoP3-R NAs and the benchmark IrO2. In addition, the two-electrode electrolyser (CoP3NiS@CoP3NiS-R) presents an ultra-low cell voltage of 1.47 V at 10 mA cm−2 and extraordinary durability over 120 h. This work elucidates the rational design of bifunctional materials in energy devices, and demonstrates that the electrochemical self-reconstruction engineering of cobalt-based phosphides is a promising strategy to design highly-efficient OER electrocatalysts.

Boron-doping on the surface mediated low-valence Co centers in cobalt phosphide for improved electrocatalytic hydrogen evolution

Rationally engineering the surface structure of transition metal phosphides (TMPs) could regulate valence state of metal centers (Mδ+) with optimized binding strength of H2O and H* and relative Gibbs free energy (ΔGH*) in alkaline hydrogen evolution reaction (HER). However, the precise location of such metal centers is still challenging due to the limited synthetic methodology. Herein we report the surface-layer-confined doping of boron on cobalt phosphide nanowire arrays (B-CoP) via a controllable surface redox reaction. Nanowire CoP decorated with B-doped surface layer structure has proved to be an outstanding HER electrocatalyst, with an overpotential of 112 mV at 100 mA cm−2. X-ray absorption near edge structure (XANES) and X-ray photoelectron spectroscopy (XPS) analysis, and theoretical results demonstrate that B-doping induced electron redistribution of Co with electron-rich features. Such low-valence Co centers coordinated with B can achieve strong affinity toward H2O molecules and optimized ΔGH* to accelerating reaction kinetics.

Urea-oxidation-assisted electrochemical water splitting for hydrogen production on a bifunctional heterostructure transition metal phosphides combining metal–organic frameworks

Electrocatalyzed urea-assisted wastewater splitting is a promising approach for sustainable hydrogen production. However, the lack of cost-efficient electrocatalysts hinders its practical application. Herein, bimetal phosphide (NiCoPx) nanowire arrays decorated with ultrathin NiFeCo metal–organic framework (NiFeCo-MOF) nanosheets on porous nickel foam (NF) were designed for urea-assisted wastewater splitting. The core–shell NiCoPx@NiFeCo-MOF hybrids were prepared via successive hydrothermal, gas-phase phosphorization and hydrothermal strategies. Encouragingly, the novel NiCoPx@NiFeCo-MOF/NF electrode served as an excellent bifunctional electrocatalyst for both the cathodic hydrogen evolution reaction (HER) and the anodic urea oxidation reaction (UOR) in urea-assisted water splitting, which merely required an overpotential of 44 mV to deliver a current density of 10 mA cm−2 for HER and a voltage of 1.37 V to deliver a current density of 100 mA cm−2 for UOR in 1.0 M KOH + 0.5 M urea. Benefiting from the highly exposed electroactive sites in exquisite three-dimensional (3D) hierarchical structure, multicomponent synergistic effect, accelerated electron transfer, easy electrolyte access and diffusion of released gas bubbles, the as-fabricated NiCoPx@NiFeCo-MOF/NF exhibited outstanding electrocatalytic performance. The mechanism of water splitting was elucidated by density functional theory calculations. Interestingly, NiFeCo-MOF possessed optimized COO* adsorption ability on Ni sites that were beneficial to UOR intermediates. More significantly, this work paves the way for the design and fabrication of bifunctional electrocatalysts for urea-containing wastewater treatment and sustainable hydrogen production.

Polydopamine‐derived carbon layer anchoring NiCo‐P nanowire arrays for high‐performance binder‐free supercapacitor and electrocatalytic hydrogen evolution

AbstractTransition metal phosphides (TMPs) have been extensively and deeply researched as electrode materials for energy‐related applications. However, the inferior stability is still a bottleneck restricting their substantive development. Herein, a freestanding three‐dimensional hierarchical nanostructure (marked as CC@NC/NiCo‐P) is delicately designed for high‐performance supercapacitors and electrocatalytic hydrogen evolution, where the nitrogen‐doped carbon (NC) layer derived from polydopamine serves as an interface coupling bridge for anchoring electroactive nickel cobalt phosphide (NiCo‐P) nanowire arrays on flexible carbon cloth (CC) substrate. Thanks to the robust interaction between the conductive carbon support and NiCo‐P nanowires, the resultant CC@NC/NiCo‐P electrode delivers an ultrahigh capacitance (2175.5 F/g at 1 A/g) and a distinguished rate capability with a capacity retention of 85.8%. The assembled asymmetric supercapacitor can achieve a superior energy density of 28.47 Wh/kg and an ultralong lifespan of 10 000 cycles. In addition, the CC@NC/NiCo‐P electrode shows favorable electrocatalytic activity toward the hydrogen evolution reaction. These results indicate that the strong binding between the NC layer and metal species in TMPs notably improves the stability and electrochemical activity of CC@NC/NiCo‐P. It is expected that this effective strategy to design innovative electrode materials may be promising for the applications in energy‐related fields.

Unveiling the advantages of an ultrathin N-doped carbon shell on self-supported tungsten phosphide nanowire arrays for the hydrogen evolution reaction experimentally and theoretically.

Packaging electrocatalysts with carbon shells offers an opportunity to develop stable and effective hydrogen evolution reaction (HER) materials. Here, an ultrathin N-doped carbon-coated self-supported WP nanowire array (WP@NC NA) hybrid has been synthesized. Owing to the encapsulation of the ultrathin N-doped carbon shell on the WP surface, the as-prepared WP@NC NA hybrid exhibits enhanced physicochemical stability, more active sites, and superior conductivity compared with WP NA without carbon coating. Besides, density functional theory calculations demonstrate that the carbon shell can optimize the hydrogen adsorption step in the acidic HER, and simultaneously facilitate water physical adsorption, water dissociation, and hydroxyl group desorption steps during the alkaline HER. These findings demonstrate the intrinsic mechanism of how a carbon shell promotes the acidic and alkaline HER kinetics, and provide scientific guidance for the packaging design of promising carbon-encapsulating self-supported electrocatalysts.

Semiconductor Nanowire Arrays for High‐Performance Miniaturized Chemical Sensing

AbstractChemiresistive sensing is one of the most promising technologies for portable and miniaturized chemical sensing, with applications ranging from air quality monitoring to explosive detection and medical diagnostics. Recently, there have been growing efforts in developing microchip based chemical sensors operating at room temperature with high sensitivity, selectivity, spatial and temporal resolution, long‐term stability, and cost‐effectiveness. Here, the engineering of highly performing miniaturized gas sensors consisting of chemiresistive vertical indium phosphide nanowire (NW) arrays is reported for the first time, and their potential for the selective detection of nitrogen dioxide (NO2), a major air pollutant, is demonstrated. By carefully engineering the NW geometry (i.e., diameter and pitch), a superior sensing performance than those previously reported semiconductor‐based NO2 sensors is achieved, obtaining a limit of detection of 3.1 ppb at room temperature, with outstanding selectivity, and long‐term stability. Kinetic analysis and electrical simulation further reveal the array geometry correlated sensing mechanism, providing insights for the design of future NW array‐based devices. These findings indicate that, owing to their unique nanoscale structures, material properties, and CMOS compatible manufacture processes, III‐V compound semiconductor NW arrays present a new and promising chemical sensing platform for development of future high performance, miniaturized on‐chip sensing system.

Interfacial Engineering of Nickel Hydroxide on Cobalt Phosphide for Alkaline Water Electrocatalysis

AbstractCatalysts based on earth‐abundant non‐noble metals are interesting candidates for alkaline water electrolysis in sustainable hydrogen economies. However, such catalysts often suffer from high overpotential and sluggish kinetics in both the hydrogen and oxygen evolution reactions (HER and OER). In this study, a hybrid catalyst made of iron‐doped cobalt phosphide (Fe‐CoP) nanowire arrays and Ni(OH)2 nanosheets is introduced that displays strong electronic interactions at the interface, which significantly improves the interfacial reactivity of reactants and/or intermediates with the hybrid catalyst surface. The combined experimental and theoretical study further confirms that the hybrid catalyst promotes the sluggish rate‐limiting steps in both the HER and OER. Full water electrolysis is thus enabled to take place at such a low cell voltage as 1.52 V to reach the current density of 10 mA cm−2 along with superior durability and high conversion efficiency.

Enhanced Hydrogen Evolution Activity of Phosphorus‐Rich Tungsten Phosphide by Cobalt Doping: A Comprehensive Study of the Active Sites and Electronic Structure

AbstractPhosphorus‐rich transition metal phosphides (TMPs) are considered efficient electrocatalysts for the hydrogen evolution reaction (HER). However, the actual activity of P‐rich TMPs is not as good as expected because of the undesirable electronic structure. Transition metal doping has been shown to be effective in improving the HER activity of TMPs in both acid and alkaline media, but the underlying mechanism is ambiguous, especially for P‐rich TMPs. Herein, cobalt‐doped and phosphorus‐rich tungsten phosphide nanowire arrays (Co/WP2 NWs/CC) are synthesized and the electrochemical properties and mechanism are determined by both experiments and theoretical calculation. The results reveal that Co dopants serve as inert catalytic sites and do not participate in HER process, but the Co/WP2 NWs/CC exhibits enhanced electrocatalytic activity as a result of the lower water dissociation barrier and hydrogen adsorption/desorption free energy on W or P sites and improved conductivity by strong electron‐donating effects of Co dopants, thereby boosting the catalytic activity and kinetics.

Three-dimensional flower-like WP2 nanowire arrays grown on Ni foam for full water splitting

A novel three-dimensional (3D) flower-like tungsten phosphide (WP2) nanowire arrays catalyst in-situ grown on nickel foam (NF) is explored. Since this 3D nanostructured electrocatalysts (WP2 NW/NF) can expose the abundant active sites, and promote electrolyte osmosis to shorten the electron transfer path, the WP2 NW/NF electrode shows excellent electrocatalytic performance. The current densities of the 3D nanostructured WP2 NW/NF electrode achieve 10 mA cm−2 at lower cell potentialof 1.65 V for overall water splitting, revealing that this 3D nanostructured electrode possesses great application prospect in electrolysis of water to produce large-scale hydrogen and oxygen.

Highly sensitive and selective dopamine sensor uses three-dimensional cobalt phosphide nanowire array

The detection of dopamine is essential for the treatment and diagnosis of depression and other diseases. In this work, cobalt phosphide nanowire arrays grown on titanium mesh (CoP NWAs/TM) are prepared by two steps of hydrothermal and phosphating, and firstly used for the detection of dopamine. The electrochemical behavior of the CoP NWAs/TM was evaluated by amperometry and differential pulse voltammetry. Amperometric analysis reveals admirable parameters in neutral PBS: (a) a working potential of 0.30 V; (b) a wide linear range (1 μM ~ 3 mM); (c) a high sensitivity (3366 μA·mM−1·cm−2); (d) a low detection limit (3.56 × 10–4 mM). Moreover, the interference effect of the common interfering species and the stability were investigated. Further experiments show that the sensor could be successfully used to detect dopamine in human blood serum. Highly sensitive and selective dopamine sensor uses three-dimensional cobalt phosphide nanowire array, which is the first experiment to apply Co-based transition metal phosphides for dopamine detection. The sensor based on cobalt phosphide nanowire array-electrode could be successfully used to detect dopamine in human blood serum.

Synthesis and Characterization of Ordered Cobalt Phosphide Nanowire Arrays As a Potential Catalyst for HER/Oer Reactions.

Nowadays, increased interest in the field of nano-scale materials is observed [1]. Knowledge about the physicochemical properties of nano-objects is desirable since they exhibit completely different properties than their macroscopic counterparts. The greatest advantage of nanomaterials is their developed specific surface area. This feature is useful in many fields of science, e.g., catalysis, that uses a large number of active centers (resulting from the developed surface), as well as modifications of the electronic structure of nanoparticles that change their redox properties.For many years, an effective evolution of hydrogen, which is recognized as a zero-emission fuel, has been a problem. The gaseous hydrogen can be obtained via a very important reaction of water decomposition. In this field, developing a catalyst that enables low-cost, efficient, and fast water lysis is the main challenge. One of the potential catalysts for an electrochemical water decomposition is the cobalt phosphide [2], which can be obtained via the phosphorization of cobalt. Undoubtedly, the application of the cobalt phosphide nanowire arrays electrode will be beneficial due to the large surface area.In this study, an attempt to the electrodeposition of cobalt nanowires using two types of baths (i.e., aqueous and non-aqueous), via constant current and constant potential modes at different temperature ranges was made. Thus, the influence of these factors on the surface morphology of the obtained nanowires as well as their growth rate was investigated. The cobalt phosphide nanowires were obtained via annealing of the Co nanowires inside the AAO (anodic aluminum oxide) membranes, with red phosphorus in an inert atmosphere at 500 ºC for 2 h. The morphology and chemical composition of cobalt and cobalt phosphide nanowires were examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). Electrochemical tests were carried out in a three-electrode cell using 0.5 M H2SO4 as an electrolyte. For all experiments, except XRD, the AAO templates were removed in 1 M NaOH.[1] Baer, D. R., Engelhard, M. H., Johnson, G. E., Laskin, J., Lai, J., Mueller, K., Moon, D. Surface characterization of nanomaterials and nanoparticles: Important needs and challenging opportunities, Journal of vacuum science & technology, 2013, 31(5), 50820[2] Pan, Y.& Lin, Y. & Chen, Y. & Liu, Y. & Liu, C., Cobalt phosphide-based electrocatalysts: Synthesis and phase catalytic activity comparison for hydrogen evolution, Journal of Materials Chemistry A., 2016, 4(13), 4745-4754This work was supported by the National Science Centre Poland (Grant No. 2017/26/M/ST5/00715). The participation in this conference was made possible by financial support from the Polish Ministry of Science and Higher Education within a conceptual non-competitive project entitled "Best of the best! 4.0." (Measure 3.3). The project is co-financed from the European Social Fund under the Operational Programme Knowledge, Education, Development 2014-2020 (POWR.03.03.00-00-P019/18).

Nickel Phosphide Nanomaterials for Hydrogen Evolution Reaction

Among non-noble-metal-based materials considered for hydrogen evolution reaction (HER) electrocatalysts, metal phosphides are quite popular, as they are chemically and mechanically stable, have good conductive properties and a high number of potential active sites on the surface [1,2]. Nickel phosphide, in particular, has been investigated – with promising results – as a HER catalyst in a variety of environments [3].When it comes to the morphology of an electrocatalyst, ordered nanowire arrays seem promising. Not only do they have a large and easily accessible active surface area, but also offer a simplified electron transfer path and can be synthesized directly on a conducting substrate, which greatly reduces or removes the need for additional binders. Moreover, such a nanomaterial should be less prone to damage during usage, especially when gas evolution occurs. Nanowire arrays are often synthesized by electrodeposition into nanoporous anodic aluminum oxide (AAO) membranes. However, aqueous solutions typically used in electrosynthesis of various metal-based materials have several limitations, which may cause brittleness or sponginess of structures [5,6]. These problems can be overcome by using non-aqueous solutions, like those based on deep eutectic solvents (DESs), which offer extended potential windows and low toxicity and are easy to prepare.In this research electrodeposition of nickel in a DES-based environment is used to obtain nickel and nickel phosphide nanowire arrays of good quality, and the prepared nanostructures are then tested as HER electrocatalysts.Ordered arrays of nickel nanowires were prepared by electrodeposition of Ni into AAO templates. A non-aqueous bath based on a mixture of choline chloride and ethylene glycol in molar ratio of 1:2 was used; Ni concentration in the bath was 1.14 M. The electrodeposition was performed at 70 ºC under galvanostatic regime. Nickel phosphide nanowire arrays were obtained via phosphorization of previously prepared nickel nanowires. In order to do so, the AAO membranes with Ni nanowires inside were annealed with red phosphorus in argon atmosphere at 500 ºC for 2 h. The morphology and chemical composition of nickel and nickel phosphide nanowires were examined by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). Electrochemical tests were carried out in a three-electrode cell, in 0.5 M H2SO4. For all experiments except XRD AAO templates were removed in 1 M NaOH.AcknowledgementsThis work was supported by the National Science Centre Poland (Grant No. 2017/26/M/ST5/00715). The participation in this conference was made possible by financial support from the Polish Ministry of Science and Higher Education within a conceptual non-competitive project entitled "Best of the best! 4.0." (Measure 3.3). The project is co-financed from the European Social Fund under the Operational Programme Knowledge, Education, Development 2014-2020.

Ion-exchange controlled surface engineering of cobalt phosphide nanowires for enhanced hydrogen evolution

Transition metal phosphides are promising alternatives to the precious metal catalysts for various electrocatalysis applications. Controllable and precise surface engineering of electrocatalysts is the key challenge to enhance their performance. Herein, we demonstrate an ion-exchange strategy to produce cobalt phosphide nanowires which have a conductive core and a thickness-controlled surface layer with sulfur dopants, phosphorus vacancies, and amorphous domains. They are applied for hydrogen evolution reaction with high stability, achieving a current density of 100 mA cm -2 at an overpotential of 114 mV. Based on both comprehensive state-of-the-art experimental characterizations and theoretical investigations, the excellent catalytic performance is attributed to increased active sites, facilitated charge transfer and transport, as well as weakened H adsorption and strengthened H 2 O adsorption due to the synergistic effects of S dopants and P vacancies. A controllable surface-layer-confined doping strategy to engineer the surface composition and structure of cobalt phosphide nanowire arrays based on an ion-exchange mechanism is developed toward superior electrocatalytic hydrogen evolution. • A controllable ion-exchange strategy to produce sulfur doped-cobalt phosphide nanowires (S-CoP) has been developed. • S-CoP has conductive core and thickness-controlled surface layer with sulfur dopants, phosphorus vacancies, and amorphous domains. • S-CoP can achieve the current density of 100 mA cm -2 at a low overpotential of 114 mV, much is lower than that of CoP ( η 100 = 134 mV). • We demonstrate a new strategy to precisely engineer a nanostructured catalyst based on state-of-the-art experimental characterization and theoretical analyses. • Mechanistic insights on interplays between dopants, vacancies and active centers have been provided.

High Capacity and Energy Density of Zn-Ni-Co-P Nanowire Arrays as an Advanced Electrode for Aqueous Asymmetric Supercapacitor.

Developing multicomponent transition-metal phosphides has become an efficient way to improve the capacitive performance of single-component transition-metal phosphides. However, reports on quaternary phosphides for supercapacitor applications are still scarce. Here, we report high capacity and energy density of Zn-Ni-Co-P quaternary phosphide nanowire arrays on nickel foam (ZNCP-NF) composed of highly conductive metal-rich phosphides as an advanced binder-free electrode in aqueous asymmetric supercapacitors. In a three-electrode system using the new electrode, a high specific capacity of 1111 C g-1 was obtained at a current density of 10 A g-1. Analysis of this aqueous asymmetric supercapacitor with ZNCP-NF as the positive electrode and commercial activated carbon as the negative electrode reveals a high energy density (37.59 Wh kg-1 at a power density of 856.52 W kg-1) and an outstanding cycling performance (capacity retention of 92.68% after 10 000 cycles at 2 A g-1). Our results open a path for a new design of advanced electrode material for supercapacitors.

Simulation and optimization of current generation in gallium phosphide nanowire betavoltaic devices

The geometry of a gallium phosphide nanowire (NW) array has been optimized for maximum current generation in a betavoltaic (BV) device. The energy capture efficiency for various device geometries with different radioisotope source compounds was calculated in GEANT4. A validation of GEANT4 for BV device simulation was performed by comparing a model output with the available bulk semiconductor BV performance data, followed by predictions of the performance of NW-based devices. The pitch and the diameter of the NWs were found to have the most significant impact on the β-generated current density, with the optimum diameter-to-pitch ratios ranging from 0.55 to 0.8, depending on the source. The energy capture efficiency improved when low energy beta (β) emitters were used. For devices utilizing 63Ni source compounds, the β-generated current densities approached 0.95 μA cm−2, representing an improvement by a factor as high as 5.8 compared to planar devices. In the case of 3H source compounds, the generated current density was 3.05 μA cm−2, a factor of 15.5 larger than comparable planar devices. However, NW devices utilizing sources with a higher decay energy, such as 147Pm, did not demonstrate any improvements over planar geometries. Using the results for optimum NW geometries, NW-based or other nanostructured devices could be made to surpass the present commercial BV batteries.

Self-supported tripod-like nickel phosphide nanowire arrays for hydrogen evolution

Self-supported tripod-like nickel phosphide nanowire arrays were fabricated through a novel strategy for hydrogen evolution and exhibited excellent activity and stability, superior to the benchmark Pt/C catalyst.

Cobalt Phosphide Nanowire Arrays on Conductive Substrate as an Efficient Bifunctional Catalyst for Overall Water Splitting

Hydrogen production via water splitting is a promising pathway to a clean energy resource. Herein we report the direct growth of cobalt phosphide (CoP) nanowires on conductive nickel foam (CoP@NF) ...

In situ grown Ni phosphide nanowire array on Ni foam as a high-performance catalyst for hydrazine electrooxidation

Synthesis of high-performance and cost-effective electrocatalysts towards hydrazine electrooxidation is vital to develop the direct hydrazine fuel cell (DHFC) as a viable energy conversion technology. Herein, we report a combined experimental and theoretical study of nickel phosphides (NixP) as promising catalysts for hydrazine electrooxidation. NixP nanowire array supported on a Ni foam (NF) was synthesized by a one-step phosphorization method using hypophosphite as a P-source. Ni12P5 and Ni2P phases are observed as the products of the direct phosphorization of commercial NF under the applied conditions with Ni2P nanoparticles exclusively distributing on the surface of Ni12P5. The NixP/NF catalyst exhibits a synergetic capabilities of exceptionally high activity, excellent durability and nearly 100% selectivity towards the complete electrooxidation of hydrazine in alkaline condition, which is among the best performance reported on hydrazine electrooxidation catalysts. First-principles calculations have been conducted to gain insight into the catalytic mechanism of Ni phosphides towards hydrazine electrooxidation.