Topic
Sodium hypophosphite
About: Sodium hypophosphite is a(n) research topic. Over the lifetime, 1695 publication(s) have been published within this topic receiving 15932 citation(s).
Papers published on a yearly basis
Papers
More filters
TL;DR: In this study, copper nanoparticles were synthesized through a relatively large-scale, high-throughput (0.2 M) process through the chemical reduction of copper sulfate with sodium hypophosphite in ethylene glycol within the presence of a polymer surfactant (PVP), which was included to prevent aggregation and give dispersion stability to the resulting colloidal nanoparticles.
Abstract: Copper nanoparticles are being given considerable attention as of late due to their interesting properties and potential applications in many areas of industry. One such exploitable use is as the major constituent of conductive inks and pastes used for printing various electronic components. In this study, copper nanoparticles were synthesized through a relatively large-scale (5 l), high-throughput (0.2 M) process. This facile method occurs through the chemical reduction of copper sulfate with sodium hypophosphite in ethylene glycol within the presence of a polymer surfactant (PVP), which was included to prevent aggregation and give dispersion stability to the resulting colloidal nanoparticles. Reaction yields were determined to be quantitative while particle dispersion yields were between 68 and 73%. The size of the copper nanoparticles could be controlled between 30 and 65 nm by varying the reaction time, reaction temperature, and relative ratio of copper sulfate to the surfactant. Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) images of the particles revealed a spherical shape within the reported size regime, and x-ray analysis confirmed the formation of face-centered cubic (FCC) metallic copper. Furthermore, inkjet printing nanocopper inks prepared from the polymer-stabilized copper nanoparticles onto polyimide substrates resulted in metallic copper traces with low electrical resistivities (≥3.6 µΩ cm, or ≥2.2 times the resistivity of bulk copper) after a relatively low-temperature sintering process (200 °C for up to 60 min).
474 citations
TL;DR: In this article, nanocrystalline manganese oxides have been synthesized by reducing aqueous KMnO 4 solution with various reducing agents such as potassium borohydride, sodium dithionite, sodium hypophosphite, and hydrochloric acid under various controlled pH conditions.
Abstract: With an objective to develop inexpensive electrode materials for electrochemical redox capacitors, nanocrystalline manganese oxides have been synthesized by reducing aqueous KMnO 4 solution with various reducing agents such as potassium borohydride, sodium dithionite, sodium hypophosphite, and hydrochloric acid under various controlled pH conditions. The products have been characterized by X-ray diffraction, thermogravimetric analysis, surface area measurements, and cyclic voltametry in various neutral electrolytes such as aqueous NaCI, KCl, LiCI, and Na 2 SO 4 . Optimized samples exhibit specific capacitance values of around 250 F/g in the range of 0-1 V vs. SCE with excellent cyclability in 2 M NaCI electrolyte.
292 citations
TL;DR: In this article, the effect of coating time on phosphorus content, thickness, structure and hardness of the deposits were analyzed, and the X-ray diffraction patterns showed that by changing the coating times, amorphous or crystalline structure could be obtained.
Abstract: Mild steel was electroless coated with nickel–phosphorus alloy from a bath containing sodium hypophosphite and glycin–citrate complexing agents. The effect of coating time on phosphorus content, thickness, structure and hardness of the deposits were analyzed. Corrosion parameters such as current density, corrosion potential and corrosion rate were obtained from tafel polarization curves and immersion corrosion tests in aerated 3.5% NaCl solution. The X-ray diffraction (XRD) patterns, anodic polarization curves and scanning electron microscopy (SEM) of heat-treated specimens obtained in various coating times were also studied. The X-ray diffraction patterns showed that by changing the coating times, amorphous or crystalline structure could be obtained. The coatings containing 11.1–13.1% phosphorous were amorphous, and showed better corrosion resistance than microcrystalline structure. The heat-treated specimens obtained in different coating time had more hardness and corrosion resistance than unheated samples. According to the polarization studies and scanning electron microscopy images, the heat-treated samples with 10.8 and 10.1% phosphorous show the intergranular corrosion, while the coatings with 11.7 and 12.2% of phosphorus have the least corrosion rate. Immersion corrosion test data at the 4-month interval had good agreement with electrochemical polarization results.
256 citations
TL;DR: In this article, a P-doped tubular g-C3N4 (P-TCN) with surface carbon defects was used to tune the morphology and C/N ratio of the tube.
Abstract: Hetero-element doping or vacancy defects of g-C3N4 framework were found significantly to control its electronic structure and enhance photocatalytic activity under visible light. Herein, we fabricated P-doped tubular g-C3N4 (P-TCN) with surface carbon defects wherein the P-doping and carbon defects were conveniently introduced during thermal polymerization of a supramolecular precursor. The supramolecular precursor of rod-like morphology was obtained only from melamine molecules under a sodium pyrophosphate-assisted hydrothermal process. As contrast, similar P-doped g-C3N4 tubes were obtained using other phosphates, such as ammonium phosphate, sodium hypophosphite and sodium phosphite, thus highlighting the versatility of this method to tune the morphology and C/N ratio for g-C3N4 tubes. The photocatalytic activities of P-TCNs were evaluated using hydrogen evolution from water under visible light. Among these, P-TCN obtained by sodium pyrophosphate-assisted hydrothermal reaction showed the highest photocatalytic activity due to high P element doping, enhanced visible light absorption and improved charge separation. The novel synthetic method described here thus represents an effective way of non-metal doping and C/N ratio tuning of g-C3N4 with excellent photocatalytic performance.
240 citations
TL;DR: In this article, three-dimensional hierarchical porous carbons (P-3DHPCs) have been synthesized by direct pyrolysis of mixture containing glucose, manganese nitrate and sodium hypophosphite without any hard templates.
Abstract: Phosphorus-doped three-dimensional hierarchical porous carbons (P-3DHPCs) have been synthesized by direct pyrolysis of mixture containing glucose, manganese nitrate and sodium hypophosphite without any hard templates. Glucose and sodium hypophosphite are used as carbon and phosphorus source in the facile template-free strategy, respectively. The P-3DHPCs not only possess favorable hierarchical pore structure which is beneficial to ion adsorption and transportation, but also acquire effective heteroatoms doping, further improving the capacitive performance. More importantly, the amount of sodium hypophosphite plays a critical role in textural properties and phosphorus content of P-3DHPCs. The results demonstrate that P-3DHPC-0.2 shows the best electrochemical performance compared to the other samples. High specific capacitance (367 F g −1 at 0.3 A g −1 ) is obtained in 6 M KOH, and the capacitance still maintains 319 F g −1 when tested at 20 A g −1 (ca.88% capacitance retention). Moreover, the P-3DHPC-0.2 also possesses good cycling stability with only a loss of 3.5% after 10000 cycles at 3 A g −1 . The facile preparation method and good electrochemical performance render P-3DHPCs to be a promising candidate for supercapacitor application.
210 citations