Electrochemical Oxidation of Hydrazines at a 4-Pyridyl Hydroquinone Modified Electrode

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Design, Synthesis and Biological Activities of Novel Benzoyl Hydrazines Containing Pyrazole

In search of environmentally benign compounds with high biological activity, low toxicity and low resistance, 8 novel benzoyl hydrazines containing pyrazole were designed and synthesized. All compounds were characterized by I H NMR spectra and HRMS. The preliminary results of biological activity assessment indicated that most of title compounds exhibited certain insecticidal activities against M）,thimna separata Walker at 200 mg L-1 but excellent fungicidal activities against six fungus at 50 mg L-1, which were better than the control.

Heteroatom-Induced Accelerated Kinetics on Nickel Selenide for Highly Efficient Hydrazine-Assisted Water Splitting and Zn-Hydrazine Battery

Hydrazine-assisted water electrolysis is a promising energy conversion technology for highly efficient hydrogen production.Rational design of bifunctional electrocatalysts,which can simultaneously accelerate hydrogen evolution reaction(HER)/hydrazine oxidation reaction(HzOR)kinetics,is the key step.Herein,we demonstrate the development of ultrathin P/Fe co-doped NiSe_(2) nanosheets supported on modified Ni foam(P/Fe-NiSe_(2)) synthesized through a facile electrodeposition process and subsequent heat treatment.Based on electrochemical measurements,characterizations,and density functional theory calculations,a favorable“2+2”reaction mechanism with a two-step HER process and a two-step HzOR step was fully proved and the specific effect of P doping on HzOR kinetics was investigated.P/Fe-NiSe_(2) thus yields an impressive electrocatalytic performance,delivering a high current density of 100 mA cm^(−2) with potentials of−168 and 200 mV for HER and HzOR,respectively.Additionally,P/Fe-NiSe_(2) can work efficiently for hydrazine-assisted water electrolysis and Zn-Hydrazine(Zn-Hz)battery,making it promising for practical application.

Low-content Pt-triggered the optimized d-band center of Rh metallene for energy-saving hydrogen production coupled with hydrazine degradation

Utilizing the hydrazine-assisted water electrolysis for energy-efficient hydrogen production shows a promising application, which relies on the development and design of efficient bifunctional electrocatalysts. Herein, we reported a low-content Pt-doped Rh metallene(Pt-Rhene) for hydrazine-assisted water electrolysis towards energy-saving hydrogen(H_(2)) production, where the ultrathin metallene is constructed to provide enough favorable active sites for catalysis and improve atom utilization.Additionally, the synergistic effect between Rh and Pt can optimize the electronic structure of Rh for improving the intrinsic activity. Therefore, the required overpotential of Pt-Rhene is only 37 mV to reach a current density of-10 mA cm^(-2) in the hydrogen evolution reaction(HER), and the Pt-Rhene exhibits a required overpotential of only 11 mV to reach a current density of 10 mA cm^(-2) in the hydrazine oxidation reaction(HzOR). With the constructed HER-HzOR two-electrode system, the Pt-Rhene electrodes exhibit an extremely low voltage(0.06/0.19/0.28 V) to achieve current densities of 10/50/100 mA cm^(-2) for energy-saving H_(2) production, which greatly reduces the electrolysis energy consumption. Moreover,DFT calculations further demonstrate that the introduction of Pt modulates the electronic structure of Rh and optimizes the d-band center, thus enhancing the adsorption and desorption of reactant/intermediates in the electrocatalytic reaction.

Isothermal, kinetic, and thermodynamic studies for solid-phase extraction of uranium(VI) via hydrazine-impregnated carbonbased material as efficient adsorbent

The current study describes the application of a new extraction method for efficient uranium adsorption via cost-effective hydrazine-impregnated activated carbon.Various experimental parameters such as time, adsorbent weight, temperature(°C), and uranium concentration were thoroughly investigated. The synthesized adsorbent was characterized via X-ray diffraction, Fourier transformation infrared spectroscopy(FT-IR), scanning electron microscopy, and thermogravimetric analysis. The results showed86% uranium extraction under optimized conditions(20% P2O5 at 25 °C, 120 min). The obtained findings fit well with thermodynamic and isothermal(Langmuir and Freundlich isotherms) models and pseudo second-order kinetics. In thermodynamic studies, the negative sign of(DG°) specified the spontaneity of process, the negative sign of(DH°) revealed endothermicity, and the positive sign of(DS°) showed high randomness after adsorption.

Synthesis of Ni nanowires via a hydrazine reduction route in aqueous ethanol solutions assisted by external magnetic fields

One-dimensional Ni nanostructures were synthesized via a hydrazine reduction route under external magnetic fields. The mixture of de-ionized water and ethanol was used as the reaction solvent and hydrazine hydrate as reducing agents. The morphology and properties of Ni nanostructures were characterized by X-ray diffractometer(XRD), scanning electron microscopy(SEM), and vibrating sample magnetometer(VSM). It was found that the magnetic field strength, concentration of Ni ions,reaction time and temperature as well as p H values played key roles on formation, microstructures and magnetic properties of Ni nanowires. The optimal wires have diameter of ~200 nm and length up to ~200 μm. And their coercivity is ~260 Oe, which is much larger than the commercial Ni powders of 31 Oe. This work presents a simple, low-cost, environment-friendly and large-scale production approach to fabricate one-dimensional magnetic materials. The resulting materials may have potential applications in conductive filters, magnetic sensors and catalytic agents.

Novel nanoporous binary Ag-Ni electrocatalysts for hydrazine oxidation

From an aqueous mixture of Ag（I）-EDTA complex and Ni（II） nitrate, silver and nickel particles were co-deposited on the surface of titanium substrates by the hydrothermal method using hydrazine hydrate as a reduction agent. The prepared titanium-supported nano-scale Ag and Ag-Ni particles （nano Ag/Ti, nano Ag86Ni14/Ti, nano Ag77Ni23/Ti, and nano Ag74Ni26/Ti） exhibit nanoporous 3D network textures. Their electrocatalytic activity towards hydrazine oxidation in alkaline solutions was evaluated by cyclic voltammetry and chronoamperometry. The results show that the four samples present a low onset potential of ca. -0.60 V vs. SCE and considerably high and stable anodic current densities for hydrazine oxidation. Among them, the nano Ag86Ni14/Ti electrode exhibits the highest anodic current density towards hydrazine oxidation, showing an increment of electro-active sites on the nano Ag86Ni14/Ti due to the addition of Ni to Ag particles.

PREPARATION OF ULTRAFINE NICKEL POWDER

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Fabrication of a Highly Sensitive Hydrazine Electrochemical Sensor Based on Bimetallic Au-Pt Hybrid Nanocomposite onto Modified Electrode

In this research a novel nickel complex was used as electrocatalyst for electrooxidation of hydrazine.A nano-structured nickel-complex was electrodeposited on a bimetallic Au-Pt inorganic-organic hybrid nanocomposite modified electrode.The electrode possesses a three-dimensional(3D) porous network nanoarchitecture,in which the bimetallic Au-Pt NPs serving as metal nanoparticle based microelectrode ensembles are distributed in the matrix of interlaced 3,3′,5,5′-Tetramethylbenzidine(TMB) organic nanofibers(NFs).Surface structure and composition of the sensor was characterized by scanning electron microscopy.Electrocatalytic oxidation of hydrazine on the surface of modified electrode was investigated with cyclic voltammetry method.The results showed that the nickelcomplex films displayed excellent electrochemical catalytic activities towards hydrazine oxidation.The hydrodynamic amperometry at rotating modified electrode at constant potential versus reference electrode was used for detection of hydrazine.Under optimized conditions the calibration plots were linear in the concentration range of 0.2-85 μM and detection limit was found to be 0.1 μM.The modified electrode exhibited reproducible behavior and a high level stability during the electrochemical experiments,making it particularly suitable for the analytical purposes.

A Comparative Study of Electrochemical Capacitance of Graphene Oxide Affected by Oligomers of p-phenylenediamine and Hydrazine Hydrate in Solvothermal Condition

A systematic investigation of the graphene oxide composite reduced by either p-phenylenediamine oligomers or hydrazine hydrate was performed with field emission scanning electron microscopy,high resolution transmission electron microscopy,X-ray diffraction,fourier transform infrared,and X-ray photoelectron spectroscopy analyses.The electrical capacitance of the composite was evaluated by a cyclic voltammetry technique,while the properties of these prototype supercapacitors were measured by a chronopotentiometry technique.It was found that,under the solvothermal condition,the graphene oxide reduced by p-phenylenediamine oligomers was observed to have higher electrical capacitance than that reduced by hydrazine.The improved electrical capacitance can be attributed to that p-phenylenediamine oligomers are the more effective spacers for graphene layers;and they could also provide some pseudo-capacitance to the graphene oxide composite based on their conjugate structure.The results imply that graphene oxide modified by diamine oligomers has a good potential in energy storage devices.

Reduction of Sulphur-containing Aromatic Nitro Compounds with Hydrazine Hydrate over Iron(III) Oxide-MgO Catalyst

Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron（Ⅲ） oxide-MgO catalyst. The catalyst exhibited high activity and stability for the reduction of sulphur-containing aromatic nitro compounds. The yields of sulphur-containing aromatic amines were up to 91-99 % at 355 K after reduction for 1-4 h over this catalyst.

Preparation of SnO Nanosheets and SnO_2 Fine Powders by Hydrazine Method

SnO nanosheets and SnO_2 nanopowder were prepared by hydrazine (N_2H_4)-based chemical routes and their gas sensing characteristics were investigated.A SnCl_2-Hydrazine complex (Sn[ N_2H_4)_x]·yH_2O) was formed by a reaction between a SnCl_2 aqueous solution and N_2H_4·H_2O.When this complex was heat-treated at 450℃,SnO_2 nanopowders were prepared by the decomposition of the complex.The sensor fabricated from the SnO_2 nano powders showed a good recovery,fast response and high sensitivity for CO 50μg/g (R_a/R_g=1.87),C_2H_5OH 100μg/g (R_a/R_g=4.80),and acetone 100μg/g (R_a/R_g=1.50).SnO nano- sheets could be prepared when a NaOH solution was added to the solution containing the complex.SnO_2 nano sheets prepared by the oxidation of SnO nanosheets at 700℃in air atmosphere also showed a good sensitivity R_a/R_g=1.79) for CO 50μg/g at 400℃.The hydrazine method provided an effective tool to controlling the morphology and oxidation state of the tin oxide powders.

Syntheses,Crystal Structures,DFT Calculation and Optical Properties of a Schiff Base and Its Dinuclear Mercury(Ⅱ)Complex

A pyridine-contained Schiff base ligand L（L =（pyridine-2-vinyl）hydrazine） has been synthesized and fully characterized. By self-assembly of the ligand with HgI2, a binuclear complex Hg2I4L（C） was obtained. The structures of L and C were analyzed through single-crystal X-ray diffraction. L crystallizes in monoclinic, space group P21/n with a=11.286（5）, b=3.981（5）, c=23.865（5） , β=100.043（5）°, V=1056（1） 3, Z=4, Dc=1.323 g/m3, F（000）=440, Μr=210.24, μ=0.084 mm（-1）, the final R=0.0928 and w R=0.2867 for 6955 observed reflections with I ＆gt; 2（I）. The complex is of monoclinic system, space group P21/n with a=8.706（5）, b=17.468（5）, c=14.675（5） , β=93.922（5）°, V=2227（2） 3, Z=4, Dc=3.338 g/m3, F（000）=1928, Μr=1119.02, μ=19.321 mm（-1）, the final R=0.0366 and w R=0.1276 for 3920 observed reflections with I ＆gt; 2（I）. The structural analysis revealed that the molecule of L possesses a well planar structure. However, in the complex, the coordinated ligand distorts greatly. The absorption spectra of L and the complex in ethanol were experimentally and theoretically studied. The result indicates that the complex exhibits different absorption spectrum compared with the free ligand.

Hydrogen evolution-assisted one-pot aqueous synthesis of hierarchical trimetallic PdNiRu nanochains for hydrazine oxidation reaction

A hydrogen evolution-assisted one-pot aqueous approach was developed for facile synthesis of trimetallic Pd Ni Ru alloy nanochain-like networks（Pd Ni Ru NCNs） by only using KBHas the reductant, without any specific additive（e.g. surfactant, polymer, template or seed）. The products were mainly investigated by transmission electron microscopy（TEM）, X-ray diffraction（XRD） and X-ray photoelectron spectroscopy（XPS）. The hierarchical architectures were formed by the oriented assembly growth and the diffusioncontrolled deposition in the presence of many in-situ generated hydrogen bubbles. The architectures had the largest electrochemically active surface area（ECSA） of 84.32 mgPdthan Pd Ni nanoparticles(NPs,65.23 mgPd), Pd Ru NPs(23.12 mgPd), Ni Ru NPs（nearly zero）, and commercial Pd black(6.01 mgPd), outperforming the referenced catalysts regarding the catalytic characters for hydrazine oxygen reaction（HOR）. The synthetic route provides new insight into the preparation of other trimetallic nanocatalysts in fuel cells.

Flow Injection Chemiluminescence Analysis of Low Level Concentration of Hydrazine

Combined with flow-injection (FI) technology, a simple chemiluminescence (CL) method was developed for hydrazine determination in this paper. It was found that hydrazine could greatly decrease the strong CL signal produced by the reaction between luminol and hexacyanoferrate (III) in alkaline medium. The decreased CL intensity was linear with hydrazine concentration in the range of 5.0×10-9 g·mL-1 to 4.0×10-5 g·mL-1, and the limit of detection was 2.0×10-9 g·mL-1 (3σ) with a relative standard deviation of 2.4~4.1% (n=5).

Syntheses, Crystal Structures and Biological Activities of the 2-Oxo-3-phenylpropionic Acid Arylformylhydrazone Dibenzyltin Complexes

Two 2-oxo-3-phenylpropionic acid arylformylhydrazone dibenzyltin(IV)complexes{[C4H3O(O)C=N-N=C(PhCH2)COO](C6H5CH2)2Sn(CH3OH)}2(Ⅰ)and{[t-Bu-C6H4(O)C=N-N=C(PhCH2)COO](C6H5CH2)2Sn(CH3OH)}2(Ⅱ)have been synthesized and characterized by IR,1H,13C and 119Sn NMR spectra,HRMS,and elemental,thermal stability and single-crystal X-ray diffraction analyses.Complex I crystallizes in the triclinic system,space group P1 with a=9.0392(9),b=10.249(1),c=15.5762(15)?,α=98.605(1)°,β=103.765(1)°,γ=104.056(1)°,Z=2,V=1326.3(2)?3,Dc=1.511 Mg·m^–3,m(MoKa)=1.005 mm–1,F(000)=612,R=0.0206 and wR=0.0524.Complex Ⅱ belongs to triclinic system,space group P1,a=11.4643(3),b=11.8885(3),c=13.0362(4)?,α=73.800(1)°,β=71.679(1)°,γ=79.006(1)°,Z=2,V=1609.34(8)?3,Dc=1.381 Mg·m^–3,m(MoKa)=0.833 mm–1,F(000)=688,R=0.0244 and wR=0.0244.In vitro antitumor activities of both complexes were evaluated by MTT against three human cancer cell lines(NCI-H460,HepG2 and MCF7)and human cell lines(HL7702).Both complexes exhibit better antitumor activity.Furthermore,the interaction between both complexes and calf thymus DNA was studied with EB fluorescent probe.

Synthesis,Crystal Structure,DFT Studies and Biological Activity of a Novel Schiff Base Containing Triazolo[4,3-a]pyridine Moiety

The novel Schiff base（E）-8-chloro-NA-（4-（dimethylamino）benzylidene）-[1,2,4]triazolo[4,3-a]pyridine-3-carbohydrazide was synthesized and characterized by ^1H NMR,MS,elemental analysis and X-ray diffraction.The compound crystallizes in the monoclinic space group P2_1/c with a = 7.091（2）,b = 10.750（3）,c = 21.380（6） A,β = 96.299（6）°,V = 1619.7（8） A^3,Z = 4 and R = 0.0351.Theoretical calculation of the title compound was carried out with the B3LYP/6-31 G basis set.The frontier orbital energy and atomic net charges were discussed.It is found that the experimental data show good agreement with the calculated values.And the compound exhibits good antifungal activity against Stemphylium lycopersici（Enjoji） Yamamoto.

Key Intermediates: A Simple and Highly Selective Synthesis of 5-<i>Amino</i>-1-<i>aryl</i>-1<i>H</i>-<i>pyrazole</i>-4-<i>carbonitriles</i>for Applications in the Crop Protection

A series of six pyrazoles was synthesized by Michael-type addition reaction. The molecules 5-amino-1-aryl-1H-pyrazole-4-carbonitrile (3a-f) were synthesized from (ethoxymethylene)malo-nonitrile (1) and fluorinated and non-fluorinated aryl hydrazines (2a-f) using ethanol and fluorinated ethanol as solvents at reflux. An excellent regio-selectivity was found when pyrazole derivatives were formed as an exclusive product. No other regioisomer or uncyclised hydrazide was observed. Their structures were confirmed by spectroscopy data (1H, 13C, 19F, COSY (correlation spectroscopy), HSQC (heteronuclear single-quantum correlation spectroscopy) and HMBC (heteronuclear multiple-bond correlation spectroscopy);MS (mass-spectrometry). The yields ranged from good to excellent (47% - 93%) under mild reaction conditions. It would indicate a high selectivity in the one-step work procedure. These products (3a-f) and derivatives have a potential academic and industrial use as key intermediates, in special, for application in crop protection.