Nitrate Hydroxide Research Articles

The construction of high sulfur content spherical sulfur-carbon nanotube-polyethylene glycol-nickel nitrate hydroxide composites for lithium sulfur battery

Lithium sulfur batteries have been widely studied because of their high energy density. However, their commercialization has been impeded by several problems, such as the poor conductivity of the active material sulfur and its discharge products, the volume expansion and the shuttle effect caused by the polysulfide intermediates dissolving in organic electrolytes. To address these problems well, we have constructed high sulfur content spherical sulfur-carbon nanotube-polyethylene glycol-nickel nitrate hydroxide (SCNT-PEG-NNH) composite material by using a simple ball-milling method. The conductivity of the composite material gets improvement due to the spherical conductive frame constructed by CNT, while the shuttle effect of polysulfides is well inhibited by the wrapping of the PEG and the fixation of NNH. The results of electrochemical tests have shown that the performance of cathode made by the SCNT-PEG-NNH composite material is greatly improved. Therefore, the SCNT-PEG-NNH composite material can be a promising cathode material for lithium sulfur batteries.

Effect of presoak-accelerated carbonation factors on enhancing recycled aggregate mortars

As the low content of calcium-bearing components in demolished recycled fine aggregates (RFA) significantly limits the carbon dioxide (CO2) curing efficiency, the effects of pre-soaking demolished RFA with calcium source solutions before the curing process are presented in this paper. Effects of varied types of calcium source solutions, including calcium hydroxide (CH), calcium chloride (CL) and calcium nitrate (CN) on the curing process are investigated. In addition, the influence of the other two parameters pertaining to curing conditions, namely, the carbon dioxide pressure and curing temperature, on the curing process are also studied. The experimental results show that, after the pre-soaking and curing process, the values of powder content, water absorption and crush value are all decreased for RFA. Furthermore, the compressive strength of mortars at 28 d are increased by as much as 56%. In addition, CN pre-soaking allows the RFA to achieve the lowest water absorption, and CL pre-soaking enables the mortars to obtain the highest compressive strength at 28 d; increasing gas pressure brings about a minor improvement in the properties of RFA and mortars, and curing temperature has complex effects on the carbonation reactions.

Effect of modified polyacrylonitrile-based carbon fiber on the oxygen reduction reactions in seawater batteries

Modified micron-sized commercial polyacrylonitrile-based carbon fiber (PAN-CF) electrodes were prepared using an electrochemical method. Such modified electrodes exhibit remarkably improved catalytic activity together with outstanding stability for oxygen reduction reactions (ORR) in seawater batteries. The effects of three solutions, including sodium hydroxide, sulfuric acid, and sodium nitrate, on the electrode electrochemical behavior were investigated and compared. The results show that the dual actions of the surface N and O functional groups will simultaneously improve the hydrophilic properties and catalytic activity of the electrode. In addition, we observed that the pyridine nitrogen- or/and pyridone-related active sites are prone to catalyzing the electrode process.

Structural, optical and photoconductivity characteristics of wet chemically grown flower like ZnO thin film nanostructure on SiO2/Si (100) substrate

Zinc oxide thin films in the form of flower shaped nanostructure has been obtained on silicon substrates from a chemical bath consists of zinc nitrate and ammonium hydroxide using dimethylamine as a complexing agent. The influence of solution pH systematically expose the growth mechanism of prepared thin film nanostructure. Films with different surface morphology has been obtained in terms of general theory of nucleation process. Structural investigation showed that the prepared films possess nanocrystalline nature with hexagonal structure with most prominent reflection along (101) plane. Photoluminescence and Raman spectroscopic analyses have been carried out to determine optical properties of the prepared films. Film with flower like nanostructure level the progress of photocurrent responsivity of the prepared films.

The effect of ion exchange and co-precipitation methods on the intercalation of 3-(4-methoxyphenyl)propionic acid into layered zinc hydroxide nitrate

A new compound, namely zinc hydroxide nitrate-3-(4-methoxyphenyl)propionate (ZHN-MPP) nanocomposite, was prepared using the ion exchange and co-precipitation methods. The resulting nanocomposite was composed of the herbicide MPP sandwiched between ZHN inorganic layers. From PXRD results, the intercalation of MPP anions into the interlayer of ZHN was successful, leading to the expansion of the interlayer of ZHN at 26.9 and 26.1 A with the ion exchange and co-precipitation methods respectively. The intercalation of layered material is confirmed by PXRD pattern. FTIR spectra for both nanocomposites revealed the presence of MPP in the interlayer of ZHN-MPP nanocomposites. Based on TGA/DTG analysis, the ZHN-MPP nanocomposite prepared by the ion exchange method was found to have greater thermal stability than the one synthesized by the co-precipitation method. The intercalation was also supported by ICP-OES and CHNO-S analysis, which confirmed the presence of C and Zn in the resultant nanocomposites. The surface analyses of both nanocomposites show mesoporous-type material characteristics. However, the co-precipitation method produced nanocomposite with a higher BET surface area compared to the ion exchange method. Overall, the intercalation process decreased the pore size of the nanocomposite compared to the pristine ZHN. The ion exchange method was proven to produce nanocomposite with higher crystallinity and higher thermal stability, whereas the co-precipitation method was proven to produce nanocomposite with a higher surface area compared to the ion exchange method. This work shows that the nanocomposite ZHN-MPP can be synthesized using the ion exchange and co-precipitation methods for the formation of a new generation of agrochemicals.

Uniform implantation of CNTs on total activated carbon surfaces: a smart engineering protocol for commercial supercapacitor applications

The main obstacles to building better supercapacitors are still trade-offs between energy and power parameters. To promote commercial supercapacitor behaviors, proper optimization toward electrode configurations/architectures may be a feasible and effective way. We herein propose a smart and reliable electrode engineering protocol, by in situ implantation of carbon nanotubes (CNTs) on total activated carbon (AC) surfaces via a mild chemical vapor deposition process at ∼550 °C, using nickel nitrate hydroxide (NNH) thin films and waste ethanol solvents as the catalyst and carbon sources, respectively. The direct and conformal growth of NNH layers onto carbonaceous scaffold guarantees the later uniform implantation of long and high-quality CNTs on total AC outer surfaces. Such fluffy and entangled CNTs preserve ionic diffusion channels, well connect neighboring ACs and function as superhighways for electrons transfer, endowing electrodes with outstanding capacitive behaviors including large output capacitances of ∼230 F g−1 in 1 M Na2SO4 neutral solution and ∼502.5 F g−1 in 6 M KOH using Ni valence state variation, and very negligible capacity decay in long-term cycles. Furthermore, a full symmetric supercapacitor device of CNTs@ACs//CNTs@ACs has been constructed, capable of delivering both high specific energy and power densities (maximum values reaching up to ∼97.2 Wh kg−1 and ∼10.84 kW kg−1), which holds great potential in competing with current mainstream supercapacitors.

Auto-ignition of a carbon-free aqueous ammonia/ammonium nitrate monofuel: A thermal and barometric analysis

A carbon-free aqueous solution of ammonium hydroxide and ammonium nitrate (AAN) was studied using differential thermal and barometric analyses under initial N2 pressure of up to 4.6MPa. The suggested nitrogen-based monofuel exhibited three distinct exothermic processes during heating. Their onset temperatures increased as the initial nitrogen pressure was raised. In addition, a higher extent of reaction was observed at high nitrogen pressures. This result was attributed to the effect of mass diffusion in the system, which decreased at higher pressures. Using a modified mechanism for the combustion of nitrogen-based fuels, the thermal ignition process was simulated. The resulting auto-ignition temperature values were shown to be in good agreement with experiments at initial nitrogen pressures of up to 2.3MPa. Above this pressure, the agreement between experimental and model results was hampered by mass diffusion effects. Using the modified mechanism, the main chemical pathways prior to auto-ignition of AAN were identified and the reactions leading to ignition were discussed. This paper presents for the first time the auto-ignition of AAN and explores the combustion chemistry of this carbon-free monofuel.

Structural Modulation of Nitrate Group with Cations to Affect SHG Responses in RE(OH)2NO3 (RE = La, Y, and Gd): New Polar Materials with Large NLO Effect after Adjusting pH Values of Reaction Systems

A series of rare-earth hydroxide nitrate crystals (La(OH)2NO3, Y(OH)2NO3, and Gd(OH)2NO3) have been synthesized through adjusting pH values of reaction systems under the subcritical hydrothermal condition. All the titled compounds were isostructural with the noncentrosymmetric space group P21 (No. 4) with layer structure, containing [REO9] (RE = La,Y, and Gd) polyhedra in each layer. The polyhedra were stacked on top of each other and further connected with zigzag strings of edge sharing to form infinite corrugated sheets that parallel to the a–c plane. The [NO3] groups that presented two different orientation (A and B) project into the space between the layers. In this study, the angle θ between two different orientation [NO3] groups was defined. With the decrease of ionic radii from La3+, Gd3+ to Y3+, the θ was increased, which led to different second harmonic generation (SHG) effects on lanthanide hydroxide nitrates. The powder SHG measurements revealed that La(OH)2NO3, Gd(OH)2NO3, and Y(OH)2NO3 were p...

硝酸亜鉛から合成した層状水酸化物のリン除去特性に及ぼす合成時pHおよび熟成温度の影響

Zinc hydroxide nitrate (ZHN), which has layered structures including NO3- and H2O between the layers, is promising materials for application to an anion exchange. ZHN can be synthesized by direct precipitation adding sodium hydroxide solution to Zn(NO3)2 solution. ZHNs were synthesized at various synthesis conditions to use them as phosphorous removal agents. ZHN precipitates were obtained at pH6, 7 and 9 and aged at 25℃, 60℃, 90℃, 120℃ respectively under hydrothermal conditions. A small part of ZHN precipitates at pH6 and aged at 120℃ transformed to ZnO, however most of ZHN precipitated at pH7 and aged at over 90℃ transformed to ZnO. However, ZHN obtained at pH9 started to transform to ZnO on aging at 60℃ and most of ZHN precipitates transformed to ZnO at over 90℃. For phosphorus removal experiments, single ZHN phase precipitates could remove around 99% phosphate ions in a 100ppm phosphorous solution, and ZHNs containing a large amount of ZnO for the most part showed lower phosphorus removal ratio. Therefore, ZHNs prepared at lower pH and aged at lower temperatures including little ZnO showed high phosphorus removal capability.

Synthesis and theoretical studies on nitrogen-rich salts of bis[4-nitraminofurazanyl-3-azoxy]azofurazan (ADNAAF).

Multi-furazan compounds bis[4-nitramino- furazanyl-3-azoxy]azofurazan (ADNAAF) and its derivatives were first synthesized by our research group, and their structures were characterized by IR, 1H-NMR, 13C-NMR spectrums, and element analysis. ADNAAF was synthesized by nitration reaction of bis[4-aminofurazanyl-3-azoxy]azofurazan (ADAAF), and then reacted with ammonium hydroxide, hydrazine hydrate, and guanidine nitrate to obtain three salts marked as salt 1, 2, and 3, respectively. The thermal stabilities of the three salts were supported by the results of DSC analysis, which shows the decomposition temperatures are all above 190°C. Their densities, enthalpies of formation, and detonation properties were studied by density functional theory (DFT) method. Salt 1 has the best detonation pressure (P), 37.42 GPa, and detonation velocity (D), 8.88km/s, while salt 2 has the best nitrogen content and heat of detonation (Q), 1.27kcal mol-1. The detonation properties of salt 1 is similar to that of 1,3,5-trinitro-1,3,5-triazineane (RDX). It means that the ammonium cation can provide the better D and P than the cation of hydrazine and guanidine. The three cations offer the enthalpies of formations in the order of hydrazinium > guanidinium > ammonium. Graphical Abstract Nitrogen-rich salts of bis[4-nitraminofurazanyl-3-azoxy]azofurazan(ADNAAF).

Nanosheets: Gas–Liquid Cold Plasma for Synthesizing Copper Hydroxide Nitrate Nanosheets with High Adsorption Capacity (Adv. Mater. Interfaces 24/2016)

Nanosheets: Gas–Liquid Cold Plasma for Synthesizing Copper Hydroxide Nitrate Nanosheets with High Adsorption Capacity (Adv. Mater. Interfaces 24/2016)

Highly Efficient Air Desulfurization on Self-Assembled Bundles of Copper Hydroxide Nanorods.

Copper hydroxide and copper hydroxyl nitrate were successfully synthesized from copper nitrate. A slight alteration of a base addition pathway led to entirely different chemical and crystal structures. Structural, morphological, and surface chemical features were analyzed using various physical and chemical methods. The copper hydroxide texture consists of self-assembled bundles of nanorods with a diameter between 15 and 40 nm. They are stack together forming platelet-like particles. In the case of the copper hydroxyl nitrate, platelet-like particles with a smooth surface were detected. The fully hydroxylated sample showed a considerably higher surface area and mesoporous volume than those of copper hydroxyl nitrate. Both synthesized materials were used as air desulfurization media at moist or dry conditions. The results indicate a supreme chemical adsorption of H2S on copper hydroxide. Moisture in air has a positive effect on the adsorption performance. In humid conditions, almost 0.9 mol H2S/mol of Cu(OH)2 was adsorbed. CuS with almost a stoichiometric ratio was a product of surface reactions. The color change of the powder from sapphire blue to dark brown during the adsorption can be used as a fast indication of the adsorbent exhaustion level.

A Comparative Analysis of the Properties of Zinc Oxide (ZnO) Nanoparticles Synthesized by Hydrothermal and Sol-Gel Methods

Objective: To study the structural, optical and conductivity properties of ZnO nanoparticles synthesized by two different methods such as hydrothermal and sol-gel methods. Methods/Analysis: ZnO is synthesized at various temperatures 100oC, 150oC and 200oC using hydrothermal method with oxalic acid and zinc acetate and using sol-gel method with sodium hydroxide, zinc chloride and zinc nitrate. Findings: For both methods, the average crystal size determined by X-ray Diffraction (XRD) is noted to be in the range 20–30 nm. The pattern confirmed the composition, crystallinity and the synthesized products are ZnO with high purity and the hexagonal phase. The absorption peak of ZnO nanoparticles has a blue-shift compared with that of the bulk. In hydrothermal method, the band gap is large (i.e) from 4.4–4.9 eV and in the sol-gel method 3.5–3.9 eV. ZnO nanoparticles synthesized by both methods exhibit similar luminescence. Scanning Electron Microscopy (SEM) pictures reveal the morphology as near-spherical prismatic nano particles for hydrothermal method and as nanoflakes for sol-gel method. The Energy Dispersive X-ray Spectroscopy (EDAX) analysis confirms the presence of ZnO only and no other element. The conductivity decreases with the growth temperature as well as the concentration of the ZnO samples by sol-gel method. In contrast, the conductivity of the sample prepared by hydrothermal method, increases with the growth temperature but decreases with the concentration. Novelty: In addition, conductivity of the synthesized ZnO nanoparticles is measured for various concentrations of ZnO. The results of both the methods are compared with each other and with those reported in the literature.

Gas–Liquid Cold Plasma for Synthesizing Copper Hydroxide Nitrate Nanosheets with High Adsorption Capacity

Gas–Liquid Cold Plasma for Synthesizing Copper Hydroxide Nitrate Nanosheets with High Adsorption Capacity

Control of morphology and optical properties of PbS nanostructured thin films by deposition parameters: study of mechanism

ABSTRACTPbS thin films were grown on glass substrates by chemical bath deposition (CBD) using lead nitrate, thiourea and sodium hydroxide in aqueous solutions at three different temperatures (22, 36 and 50 °C). The microstructure and morphology evolution of the films were investigated using X-ray diffraction, scanning electron microscopy and atomic force microscopy. Optical properties were studied using UV–Vis–IR spectroscopy. The results indicate that temperature plays an important role in controlling the morphology and optical properties of nanostructured PbS thin films through changing deposition mechanism. The active deposition mechanism changed from cluster to ion-by-ion mechanism with an increase in deposition temperature from 22 to 50 °C, and consequently, film properties such as morphology, optical absorption and preferred orientation changed completely.

Synthesis of zinc hydroxide nitrate complex by a sol-gel method for use as foliar fertilizers – a scale up approach

Zinc hydroxide nitrate complex is a new class of materials with outstanding characteristics promising its application as foliar nano-fertilizers. In this study, nano crystalline zinc hydroxide nitrate powder was synthesized by a sol – gel method using NaOH and Zn(NO3)2.6 H2O as precursors, yielding several grams products per batch. The products were characterized by XRD, FTIR, SEM and BET, indicating the initial molar ratio NaOH : Zn(NO3)2.6H2O = 1.6 and reaction time 1 hour as suitable. Under the indicated conditions, the particle size of products is in the range 50÷100 nm. The characteristics of products demonstrate their potential application as foliar nano-fertilizer and the synthesis procedure might be further upgrading to production extents.

Complex nanomineral formation utilizing kinetic control by PLAL

We used pulsed-laser ablation in liquids (PLAL) of Cu or Zn foil targets in water or in aqueous Cu or Zn salt solutions. PLAL in neat water generated mixtures of metal and (thermodynamically preferred) metal oxide nanomaterials, whereas the availability of select dissolved anions predictably led to the fabrication of more complex phase-pure nanominerals. PLAL of Cu foil in aqueous CuCl2 solution produced nano-paratacamite, Cu2Cl(OH)3, whereas nano-rouaite, Cu2(NO3)(OH)3, was formed in aqueous Cu(NO3)2 and NH4OH solution. Likewise, we synthesized simonkolleite, Zn5(OH)8Cl2·H2O, or layered zinc hydroxide nitrate, Zn5(OH)8(NO3)2·2H2O, nanoparticles by PLAL of Zn targets in aqueous ablation liquids with added ZnCl2 and NH4OH or Zn(NO3)2, respectively. Bimetallic zincian paratacamite resulted from PLAL of Cu foil in aqueous Cu and Zn chloride solution. Our results show that kinetic control exceeded thermodynamic product formation during nanosecond ultraviolet PLAL.

Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1mg of CrO42−/g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4mg of CrO42−/g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated.

Exploring the electronic structure of Pb2+ ions containing material Pb16(OH)16(NO3)16

A theoretical band structure calculation for lead nitrate hydroxide Pb16(OH)16(NO3)16 single crystal was performed based on the experimental crystallographic data obtained by Chang et al. Calculations exhibit that the conduction band minimum (CBM) is situated at Γ the center of the Brillouin zone (BZ) while the valence band maximum (VBM) is located between Γ and Y points of the BZ, resulting in an indirect energy band gap of about 3.70eV in close agreement to the measured one (3.78eV). The angular momentum resolved projected density of states reveals the existence of the strong hybridization between the orbitals and the VBM is originated from Pb-6s/6p and O-2p orbitals while the CBM from N-2p and Pb-6p orbitals. The calculated valence electronic charge density distribution explore the bond characters and the dominancy of the covalent bonding between Pb–O of PbOn ployhedra and N–O of [NO3]− triangle. The calculated bond lengths and angles show good agreement with the experimental data.

Effect of Hydroxide Concentration and Adding Ascorbic Acid on Morphology Shape of Zinc Oxide Nanostructure Prepared by Simple Chemical Precipitation Method

A chemical precipitation method was used to prepare zinc oxide (ZnO) nanostructure in the present of zinc nitrate and ammonium hydroxide as zinc precursor and hydroxide precursor respectively. The effect of the hydroxide concentration and the effect of adding ascorbic acid as modifier into the mixture solution on the morphology property of zinc oxide was studied. The morphology and the structural of ZnO nanostructures were investigated by field-emission scanning electron microscope (FE-SEM) and X-ray diffractometer (XRD) techniques, respectively. The results showed that the basicity solution and adding stabilizer are important parameters on the morphology and structural properties of ZnO nanostructure. At a low hydroxide concentration, ZnO exhibited flower-like structure with short petal. With a further increase to higher concentration, ZnO crystal have more crystal directional growth. When the ascorbic acid was added, the morphology changed to particle-like structure. ZnO nanostructure with different shape might be used for specific applications such as gas sensor etc.