- Helical magnetic structure and hyperfine interactions in FeP studied by 57Fe M?ssbauer spectroscopy and 31P NMR
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We report results of 57Fe M?ssbauer and 31P NMR studies of a phosphide FeP powder sample performed in a wide temperature range including the point (TN ≈ 120 K) of magnetic phase transitions. The 57Fe M?ssbauer spectra at low temperatures T N present a very complex Zeeman pattern with line broadenings and sizeable spectral asymmetry. It was shown that the change of the observed spectral shape is consistent with the transition into a space-modulated helicoidal magnetic structure. Analysis of the experimental spectra was carried out assuming an anisotropy of the magnetic hyperfine field Hhf at the 57Fe nuclei when the Fe3+ magnetic moment rotates with respect to the principal axis of the electric field gradient (EFG) tensor. The obtained large temperature independent anharmonicity parameter m ≈ 0.96 of the helicoidal spin structure results from easy-axis anisotropy in the plane of the iron spin rotation. It was assumed that a very low maximal value of Hhf(11 K) ≈ 36 kOe and its high anisotropy ΔHanis(11 K) ≈ 30 kOe can be attributed to the stabilization of iron cations in the low-spin state (SFe = 1/2). The 31P NMR measurements demonstrate an extremely broad linewidth reflecting the spatial distribution of the transferred internal magnetic fields of the Fe3+ ions onto P sites in the magnetically ordered state.
- Sobolev, Alexey V.,Presniakov, Igor A.,Gippius, Andrey A.,Chernyavskii, Ivan V.,Schaedler, Martina,Buettgen, Norbert,Ibragimov, Sergey A.,Morozov, Igor V.,Shevelkov, Andrei V.
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- FeP and FeP2 nanowires for efficient electrocatalytic hydrogen evolution reaction
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We report achieving of efficient electrocatalytic hydrogen evolution reaction using composition-controlled iron phosphide (FeP and FeP2) nanowires. The respective Tafel slopes of nanowire arrays were 39 and 37 mV dec-1 in 0.5 M H2SO4, and 75 and 67 mV dec-1 in 1 M KOH. The richer P composition produced excellent electrocatalytic efficiency.
- Son, Chang Yong,Kwak, In Hye,Lim, Young Rok,Park, Jeunghee
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- Superconductivity of the "1 1 1" type iron pnictide LiFeP
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We report studies on a new iron based LiFeP superconductor. The compound takes the same structure to LiFeAs containing a "FeP" conduction layer. Superconductivity was achieved up to 6 K. The new superconductor is featured with itinerant behavior at normal
- Deng,Wang,Liu,Zhang,Lv,Zhu,Yu,Jin
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- A general methodology for the synthesis of transition metal pnictide nanoparticles from pnictate precursors and its application to iron-phosphorus phases
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Nanoparticles of iron phosphide have been prepared through a new strategy involving the reductive annealing of nanoparticulate iron phosphate precursors cast onto atomically flat mica surfaces. This route appears to be general for a range of transition metals and pnicogens and avoids the use of highly toxic and pyrophoric agents such as Pn(SiMe3)3 (Pn = P, As), which are commonly employed in the synthesis of pnictide nanoparticles. Copyright
- Stamm, Kimber L.,Garno, Jayne C.,Liu, Gang-yu,Brock, Stephanie L.
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- The Enhanced CO Tolerance of Platinum Supported on FeP Nanosheet for Superior Catalytic Activity Toward Methanol Oxidation
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The inferior CO-like intermediates tolerance of Pt nanoparticle greatly hampered the MOR activity and durability. To alleviate this issue, tremendous efforts have been made to create oxygen-containing groups on neighbouring Pt site for oxidizing the poisonous carbonaceous species. Given this, two-dimensional FeP nanosheet with excellent HER activity was utilized as support and cocatalyst. FeP nanosheet with special Feδ+ and Pδ? active sites was conductive to mass transfer, fast charge transfer and facilitating water dissociation for generating OH species to removal CO-like intermediates on Pt sites. The XRD, XPS, SEM and TEM analysis demonstrated that the Pt nanoparticle with an average size of 3.68 nm was successfully deposited on the FeP nanosheet surface. The methanol oxidation experiments in acidic medium revealed that the as-prepared binary Pt/FeP nanosheet hybrid exhibited superior MOR activity with enhanced anodic peak current density of 0.994 mA/cm2, which was 2.74-fold greater than that of commercial Pt/C, and the intensive CO oxidation peak potential was negatively shifted about 100 mV with respect to that of Pt/C. The better CO tolerance of Pt/FeP nanosheet hybrid might be attributed to cooperative effect from down-shifted d-band center of Pt, abundant hydroxyls on the Pt/FeP and special activity of Feδ+ and Pδ?. In addition, this hybrid electrocatalyst also showed relatively higher HER activity compared with that of Pt/C. This study provides a promising application of metal phosphide in methanol oxidation for enhancing CO resistance capability of Pt-based catalyst.
- Wang, Yajing,Du, Chunyu,Sun, Yongrong,Han, Guokang,Kong, Fanpeng,Yin, Geping,Gao, Yunzhi,Song, Ying
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- CVD growth of high density SWNTs network on surface using iron phosphide nanorods as catalyst precursor
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In this Letter, we demonstrated that FeP nanorods synthesized by thermal decomposition of iron carbonyl under the protection of surfactants can be used as catalyst for SWNTs growth. The domains structure of FeP nanorods or uniform dispersion of the nanorods by self-assembly on surface can be controlled by chemical modification of the surface and concentration of the nanorods solution. Domain structure of SWNTs network or extremely high density SWNTs film with uniform diameter can be generated using carbon monoxide chemical vapor deposition (CO-CVD). The uniform diameter of the SWNTs is believed to be due to the in situ formation of uniform Fe nanoparticles from the decomposition of FeP nanorods at high temperature. The use of nanorods or nanowires as catalyst precursor for SWNTs growth could open a new method to generate extremely high density SWNTs with uniform diameter for SWNTs-based nanoelectronics device applications.
- Huang, Shaoming,Bai, Yanhu,Chen, Jinagyin,Wang, Shun,Wang, Zhimin
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- De Haas-van alphen effect of FeP in double helical magnetic state
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The de Haas-van Alphen (dHvA) effect has been investigated on high-quality single crystals of FeP in a double helical magnetic state with a 5c period in the magnetic fields up to 14 T and at temperatures down to 0.42 K. Single crystals were grown by the chemical transport technique using iodine as the transport agent. Nineteen branches were observed in three crystallographic planes (100), (010) and (001), and analyzed with simple analytic equations for the Fermi surfaces. Many of the dHvA branches have a characteristic angular dependence and are found to correspond to the orbits on surfaces beyond the Brillouin zone in the magnetic state which is reduced to 1/5 of the non-magnetic one with the MnP-type along the [001] direction. These branches originate from the orbits caused by a magnetic breakdown phenomenon under high fields. Cyclotron mass ratios were obtained to be up to 5.9, whereas the electronic specific heat coefficient is rather small, 2.86 mJK-2mol-1.
- Nozue, Tatsuhiro,Kobayashi, Hisao,Kimura, Noriaki,Aoki, Haruyoshi,Kamimura, Takashi
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- Solution-Phase Synthesis of Single-Crystalline Iron Phosphide Nanorods/Nanowires
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A solution-phase route for the preparation of single-crystalline iron phosphide nanorods and nanowires is reported. We have shown that the mixture of trioctylphosphine oxide (TOPO) and trioctylphosphine (TOP), which are commonly used as the solvents for semiconductor nanocrystal synthesis, is not entirely inert. In the current process, TOP, serving as phosphor source, reacts with Fe precursors to form FeP nanostructures with large aspect ratios. In addition, the experimental results show that both TOP and TOPO are necessary for the formation of FeP nanowires and their ratio appears to control the morphology of the produced FeP structures. A possible growth mechanism is discussed.
- Qian, Cheng,Kim, Franklin,Ma, Lei,Tsui, Frank,Yang, Peidong,Liu, Jie
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- De Haas-van Alphen effect and transverse magnetoresistance in FeP
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The 3d transition metal monopnictides show various interesting electric and magnetic properties. In this study, we have measured the dHvA effect and the transverse magnetoresistance in FeP which has the MnP-type structure and is antiferromagnetic below 12
- Nozue, Tatsuhiro,Saito, Akira,Kobayashi, Hisao,Yamagami, Hiroshi,Kamimura, Takashi
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- Fe65.5Cr4Mo4Ga4P12 C5B5.5 BMGs: Sample preparation, thermal stability and mechanical properties
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Bulk amorphous Fe-based alloys with the nominal composition Fe65.5Cr4Mo4Ga4 P12C5B5.5 have been obtained by copper mold casting in different shapes: cylindrical rods with diameters up to 3 mm, rectangular bars of 2 mm × 2 mm and discs of 10 mm diameter and 1 mm thickness. These alloys exhibit good soft magnetic properties, characterized by low coercivity and high saturation magnetization. Besides the magnetic properties, the Fe65.5Cr4Mo4Ga4 P12C5B5.5 bulk metallic glass (BMG) shows a high glass transition temperature Tg, as well as a high crystallization temperature Tx, with an extension of the supercooled liquid region of around 65 K. The mechanical behavior was investigated by compression and Vickers hardness tests. The fracture strength for the as-cast samples σf is 2.8 GPa and the fracture strain εf is 1.9%. Upon annealing at 715 K for 10 min, i.e. at a temperature below the calorimetric glass transition, the fracture strain drops to 1.6% and no plastic deformation is observed. The Vickers hardness HV for the as-cast samples is about 885, and increases to 902 upon annealing. The fracture behavior of these Fe-based bulk glassy alloys is significantly different in comparison with the well-studied Zr-, Cu- or Ti-based good glass-formers. The fracture is not propagating along a well-defined direction and the fractured surface looks irregular. Instead of veins, the glassy alloy develops a high number of microcracks.
- Stoica,Eckert,Roth,Yavari,Schultz
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- Preparation of iron phosphide particles from an aqueous solvent of oxygen-contained precursors using spray pyrolysis
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Iron phosphides were prepared by an economically feasible spray pyrolysis method, in which nontoxic and inexpensive precursors are used in an aqueous solution. The addition of NaCl to the precursor solution promoted crystal growth at a low temperature and helped to avoid sintering during posttreatment. The key conclusion is that the stoichiometry, shape, and size of the particles are related to the NaCl/Fe molar ratio and the posttreatment temperature. Below the melting temperature of NaCl, the shape and stoichiometry of the particles depended on the NaCl/Fe molar ratio, while above the melting temperature, they were dominated by the posttreatment temperature. Wire-like particles were formed at a NaCl/Fe molar ratio over 15.
- Koo, Kee Young,Park, Seung Bin
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- Facile synthesis of novel, known, and low-valent transition metal phosphatesviareductive phosphatization
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Novel and known low-valent transition metal phosphates (TMPs) are accessibleviaa novel and facile pathway. The method allows syntheses of TMPs also with reduced oxidation states. The key feature of the new route is the reductive character of a hypophosphite salt melt, which acts as reaction medium and enables directing the oxidation state of the transition metal.
- Petersen, Hilke,Schmidt, Wolfgang,Stegmann, Niklas,Weidenthaler, Claudia
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- Design and fabrication of Fe2O3/FeP heterostructure for oxygen evolution reaction electrocatalysis
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The production of an inexpensive, highly active electrocatalyst for a simple oxygen evolution reaction (OER) based on earth-abundant transition metals is still a major challenge. In addition, the ambiguity of the water splitting reaction (hydrogen evolution and OER) is a hurdle in the manufacture of suitable catalysts for the efficient water electrolysis process. Here, the synthesis of iron oxide/iron phosphide (Fe2O3/FeP) heterostructure and its counterparts Fe2O3 and FeP as cheap electrocatalysts for water electrolysis is presented. Characterization techniques such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy were used to analyze the structure of these electrocatalysts. Heterostructure Fe2O3/FeP has been shown to be a more active electrocatalyst than its counterparts. It initiates OER at a remarkably low potential of 1.49 V vs. reverse hydrogen electrode (RHE). For this electrocatalyst, a current density of 10 mA/cm2 is achieved at an overpotential of 264 mV for OER in 1.0 M potassium hydroxide solution and the value of the Tafel slope is 47 mV dec?1, outperforming its complements (Fe2O3 and FeP) under similar conditions. The results obtained are superior to those of previously reported Fe-based OER electrocatalysts. The Fe2O3/FeP electrocatalyst has proven its long-term stability by driving OER at 1.65 V (vs. RHE) for about 12.5 h.
- Ahmad, Iqbal,Ahmed, Jawad,Batool, Saima,Dahshan, Alaa,Hanif, Amna,Idrees, Muhammad,Jabeen, Uzma,Nazar, Muhammad Faizan,Shehzadi, Syeda Aalia,Ul-Hamid, Anwar,Zafar, Muhammad Nadeem,Zahidullah
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- Preparation of Yolk–Shell-Structured CoxFe1?xP with Enhanced OER Performance
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The design and development of low-cost, highly efficient, and stable electrocatalysts to take the place of noble-metal catalysts for the oxygen evolution reaction (OER) remain a significant challenge. Herein, the synthesis of yolk–shell-structured binary transition metal phosphide CoxFe1?xP with different Co/Fe ratios by phosphidation of a cobalt ferrite precursor is reported. The as-synthesized CoxFe1?xP catalysts were used for the OER. All yolk–shell CoxFe1?xP catalysts with different Co/Fe ratios showed much better performance than the corresponding solid catalyst. The formation of Co oxides on the catalyst surface during OER and the optimal Co/Fe ratio were found to be critical to their activity. Among the as-prepared CoxFe1?xP catalysts, that with a Co/Fe ratio of 0.47/0.53 (Co0.47Fe0.53P) exhibited the best performance. Co0.47Fe0.53P has an overpotential of 277 mV at a current density of 10 mA cm?2, a Tafel slope of 37 mV dec?1, and superior stability in alkaline medium. The outstanding performance is partly ascribed to the transfer of valence electrons from Co to P and Fe. The Co0.47Fe0.53P matrix with excellent conductivity and Fe phosphate that is stable on the surface of the catalyst are also helpful for the OER performance. In addition, the yolk–shell structure of Co0.47Fe0.53P increases the contact area between electrolyte and catalyst. These characteristics of Co0.47Fe0.53P greatly improve its OER performance. This optimized binary transition metal phosphide provides a new approach for the design of nonprecious-metal electrocatalysts.
- Yue, Song,Wang, Shanshan,Jiao, Qingze,Feng, Xueting,Zhan, Kun,Dai, Yiqing,Feng, Caihong,Li, Hansheng,Feng, Tongying,Zhao, Yun
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p. 4461 - 4470
(2019/09/06)
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- Lattice Matched Carbide-Phosphide Composites with Superior Electrocatalytic Activity and Stability
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Composites of electrocatalytically active transition-metal compounds present an intriguing opportunity toward enhanced activity and stability. To identify potentially scalable pairs of a catalytically active family of compounds, we demonstrate that phosphides of iron, nickel, and cobalt can be deposited on molybdenum carbide to generate nanocrystalline heterostructures. Composites synthesized via solvothermal decomposition of metal acetylacetonate salts in the presence of highly dispersed carbide nanoparticles show hydrogen evolution activities comparable to those of state-of-The-Art non-noble metal catalysts. Investigation of the spent catalyst using high resolution microscopy and elemental analysis reveals that formation of carbide-phosphide composite prevents catalyst dissolution in acid electrolyte. Lattice mismatch between the two constituent electrocatalysts can be used to rationally improve electrochemical stability. Among the composites of iron, nickel, and cobalt phosphide, iron phosphide displays the lowest degree of lattice mismatch with molybdenum carbide and shows optimal electrochemical stability. Turnover rates of the composites are higher than that of the carbide substrate and compare favorably to other electrocatalysts based on earth-abundant elements. Our findings will inspire further investigation into composite nanocrystalline electrocatalysts that use molybdenum carbide as a stable catalyst support.
- Regmi, Yagya N.,Roy, Asa,King, Laurie A.,Cullen, David A.,Meyer, Harry M.,Goenaga, Gabriel A.,Zawodzinski, Thomas A.,Labbé, Nicole,Chmely, Stephen C.
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p. 9369 - 9377
(2017/11/20)
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- A new, cheap, and productive FeP anode material for sodium-ion batteries
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A novel and low-cost FeP anode with a high capacity of 764.7 mA h g-1 synthesized by a ball-milling method is reported for sodium ion batteries. Ex situ X-ray diffraction and transmission electron microscopy have been used to explore the sodium storage mechanism of FeP. This journal is
- Li, Wei-Jie,Chou, Shu-Lei,Wang, Jia-Zhao,Liu, Hua-Kun,Dou, Shi-Xue
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supporting information
p. 3682 - 3685
(2015/04/14)
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- Chemical pressure effect in CeFeAs1-xPxO 0.95F0.05
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We investigate the chemical pressure effect due to P doping in the CeFeAs1-xPxO0.95F0.05 (0≤x≤0.4) system. The compound CeFeAsO0.95F0.05 without P doping is on the boundary between antiferromagnet (AFM) and superconductor. The AFM order of Ce3 local moments causes a significant reentrance behavior in both resistivity and magnetic susceptibility. Upon P doping, Tc increases and reaches a maximum of 21.3 K at x=0.15, and then it is suppressed to lower temperatures. Meanwhile, the AFM order of Ce3 ions remains nearly the same in the whole doping range (0≤x≤0.4). Our experimental results suggest a competition between superconductivity and Kondo effect in the Ce 1111 system.
- Luo, Yongkang,Lin, Xiao,Han, Han,Jiang, Shuai,Li, Yuke,Dai, Jianhui,Cao, Guanghan,Xu, Zhu-An
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p. 430 - 433
(2011/08/08)
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- Oxidation does not (always) kill reactivity of transition metals: Solution-phase conversion of nanoscale transition metal oxides to phosphides and sulfides
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Unexpected reactivity on the part of oxide nanoparticles that enables their transformation into phosphides or sulfides by solution-phase reaction with trioctylphosphine (TOP) or sulfur, respectively, at temperatures of ≥370 °C is reported. Impressively, s
- Muthuswamy, Elayaraja,Brock, Stephanie L.
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p. 15849 - 15851
(2010/12/24)
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- Next-nearest neighbour contributions to the XPS binding energies and XANES absorption energies of P and As in transition-metal arsenide phosphides MAs 1-yPy having the MnP-type structure
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X-ray photoeleetron spectroscopic (XPS) and X-ray absorption near-edge spectroscopic (XANES) measurements have been made for several series of metal arsenide phosphides MAs1-yPy, (M= Co, Fe, Cr) that adopt the MnP-type structure. The P and As XPS binding energies (BEs) and XANES absorption energies of the metal arsenide phosphides do not follow the trend observed for the simple binary phosphides or arsenides, a deviation that arises from the combination of nearest and nextnearest neighbour contributions acting on the P or As photoemission or absorption site. The P 2p3/2 BEs and K-edge absorption energies are lower in MAs1-yPy than in MP because the P atoms are more negatively charged and because the P photoemission or absorption site is screened to a greater extent by less positively charged nearest-neighbour M atoms and more negatively charged next-nearest neighbour P atoms. The As L3- and K-edge absorption energies are higher in MAs1-yPy than in MAs primarily because the As atoms are less negatively charged. The M charge has been evaluated from analysis of the M 2p XPS spectra and the M L- and K-edge XANES spectra.
- Grosvenor, Andrew P.,Cavell, Ronald G.,Mar, Arthur
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p. 2549 - 2558
(2009/02/06)
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- Iron-based layered superconductor: LaOFeP
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We report superconductivity in an iron-based layered oxy-pnictide LaOFeP. LaOFeP is composed of an alternate stack of lanthanum oxide (La3+O2--) and iron pnictide (Fe2+P3-) layers. Magnetic and electrical resist
- Kamihara, Yoichi,Hiramatsu, Hidenori,Hirano, Masahiro,Kawamura, Ryuto,Yanagi, Hiroshi,Kamiya, Toshio,Hosono, Hideo
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p. 10012 - 10013
(2007/10/03)
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- Generalized synthesis of metal phosphide nanorods via thermal decomposition of continuously delivered metal-phosphine complexes using a syringe pump
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We synthesized uniform-sized nanorods of transition metal phosphides from the thermal decomposition of continuously delivered metal-phosphine complexes using a syringe pump. MnP nanorods with dimensions of 8 nm × 16 nm and 6 nm × 22 nm sized were synthesized by the thermal decomposition of Mn-TOP complex, which was prepared from the reaction of Mn2(CO)10 and tri-n-octylphosphine (TOP), using a syringe pump with constant injection rates of 10 and 20 mLVh, respectively. When Co-TOP complex, which was prepared from the reaction of cobalt acetylacetonate and TOP, was reacted in a mixture solvent composed of octyl ether and hexadecylamine at 300 °C using a syringe pump, uniform 2.5 nm × 20 nm sized Co2P nanorods were generated. When cobaltocene was employed as a precursor, uniform Co2P nanorods with 5 nm × 15 nm were obtained. When Fe-TOP complex was added to trioctylphosphine oxide (TOPO) at 360 °C using a syringe pump and then allowed to age at 360 °C for 30 min, uniform-sized FeP nanorods with an average dimension of 12 nm × 500 nm were produced. Nickel phosphide (Ni2P) nanorods with 4 nm × 8 nm were synthesized successfully by thermally decomposing the Ni-TOP complex, which was synthesized by reacting acetylacetonate [Ni(acac)2] and TOP. We measured the magnetic properties of these nanorods, and some of the nanorods exhibited different magnetic characteristics compared to the bulk counterparts.
- Park, Jongnam,Koo, Bonil,Yoon, Ki Youl,Hwang, Yosun,Kang, Misun,Park, Je-Geun,Hyeon, Taeghwan
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p. 8433 - 8440
(2007/10/03)
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- Examination of the bonding in binary transition-metal monophosphides MP (M = Cr, Mn, Fe, Co) by X-ray photoelectron spectroscopy
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The binary transition-metal monophosphides CrP, MnP, FeP, and CoP have been studied with X-ray photoelectron spectroscopy. The shifts in phosphorus 2p 3/2 core line binding energies relative to that of elemental phosphorus indicated that the de
- Grosvenor, Andrew P.,Wik, Stephen D.,Cavell, Ronald G.,Mar, Arthur
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p. 8988 - 8998
(2008/10/09)
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- Synthesis of MnP Nanocrystals by Treatment of Metal Carbonyl Complexes with Phosphines: A New, Versatile Route to Nanoscale Transition Metal Phosphides
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The reaction of Mn2(CO)10 with P(SiMe3)3 in coordinating solvents at T ≥ 220 °C yields low polydispersity, highly crystalline MnP nanoparticles for the first time. The effect of dimensional limiting has resulted in the stabilization of a ferromagnetic ground state at low temperatures, rather than the metamagnetic state observed in bulk (microcrystalline) MnP. The synthetic methodology reported here is demonstrated to be general for a number of different metals and phosphine sources. Copyright
- Perera, Susanthri C.,Tsoi, Georgy,Wenger, Lowell E.,Brock, Stephanie L.
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p. 13960 - 13961
(2007/10/03)
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- A solvothermal synthesis of ultra-fine iron phosphide
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Powder iron phosphide (FeP) has been prepared via a benzene-thermal synthesis with the reaction of anhydrous iron chloride (FeCl3) and sodium phosphide (Na3P) at 180-190°C. The product was analyzed by X-ray photoelectron spectroscopy (XPS), and the results show the mole ratio of Fe:P is 1.12. X-ray diffraction (XRD) pattern can be indexed to the orthorhombic cell of FeP with the lattice constant a = 5.191, b = 3.101, and c = 5.789 A?. Transmission electron microscope (TEM) images indicate that average particle size is about 200nm in diameter.
- Yunle, Gu,Fan, Guo,Yitai, Qian,Huagui, Zheng,Ziping, Yang
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p. 1101 - 1105
(2008/10/08)
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- Structures of the ternary iron germanium pnictides FeGe1-xPnx (Pn = P, As, Sb)
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The pseudo-binary FeGe-FePn (Pn = P, As, Sb) systems have been investigated by X-ray diffraction methods. The phosphide and arsenide systems form ternary solid solutions FeGe1-xPx (0.4≤x≤1.0) and FeGe1-xAsx (0.3≤x≤1.0) crystallizing in MnP-type structures. The antimonide system is more complex, forming intermetallic compounds that display incipient ordering of Sb2 pairs as they are stuffed into the FeGe (x = 0) structure while Ge atoms are gradually removed. The structures of an intermediate member FeGe0.80Sb0.20 (x = 0.20) and of the limiting member FeGe0.67Sb0.33 (x = 0.33) in this progression were determined by single-crystal X-ray diffraction. Both compounds crystallize in hexagonal space groups: P63/mmc, a = 8.796(2), c = 8.004(2) angstroms, Z = 6 for Fe3Ge2.4Sb0.6 (or FeGe0.80Sb0.20), and P6/mmm, a = 8.9885(5), c = 7.9043(6) angstroms, Z = 6 for Fe3Ge2Sb (or FeGe0.67Sb0.33). Beyond this point, ternary solid solutions FeGe1-xSbx (0.4≤x≤1.0) are formed, crystallizing in NiAs-type structures.
- Mills, Allison M.,Mar, Arthur
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- Sc-Sc Bonding in the New Ternary Phosphide ScNiP
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The new phosphide ScNip can be synthesized by arc-melting of ScP and Ni, or by arc-melting of Sc with NiP. The lattice constants, as obtained from the bulk sample, area=6.3343(8) A,b=3.7375(7) A,c=7.0917(8), andV=167.89(4) A3. ScNiP crystallizes in the Co2Si structure type. Although one might assign the trivalent state to Sc, corresponding to a formal ionic formula of Sc3+Ni±0P3-, the structure of ScNiP contains Sc-Sc bonds and shows weak metallic properties, as expected based on extended Hueckel calculations.
- Kleinke, Holger,Franzen, Hugo F.
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p. 218 - 222
(2008/10/08)
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