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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Synthesis and crystal structure of a new organic compound: Bis(4,4 Prime -diaminodiphenylmethane) (4,4 Prime -diammoniodiphenylmethane) dichloride monohydrate

A new organic compound with the formula C{sub 39}H{sub 46}Cl{sub 2}N{sub 6}O was synthesized from aqueous solution of 4,4 Prime -diaminodiphenylmethane and hydrochloric acid at room temperature. This compound crystallizes in the monoclinic space group C2: a = 25.6525(16), b = 5.7107(3), c = 13.7777(8) A, {beta} = 118.862(2) Degree-Sign , V = 1767.64(22) A{sup 3} and Z = 2, giving D{sub x} = 1.288 g cm{sup -3}. The refinement converged to R{sub 1} = 0.027 and wR{sub 2} = 0.0649. The structural arrangement can be described as infinite layers parallel to bc plane. In these layers cations and non protonated molecules are linked with N-H...N hydrogen bonds building [C{sub 39}H{sub 44}N{sub 6}]{sup 2+} organic clusters. These clusters, in turn, are linked by N-H...Cl and O-H...Cl hydrogen bonds.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Improving on the interparticle connection for performance enhancement of flexible quantum dot sensitized solar cells

Highlights: • TiO{sub 2} slurries have been prepared by a three-step process for the photo-anode of flexible solar cells. • Interparticle connection of photo-anodes has been improved in flexible solar cells. • This flexible QDSSCs exhibits excellent photovoltaic performance and charge transfer property. • There has excellent curving stability on the photovoltaic performance of flexible QDSSCs. - Abstract: Flexible photovoltaic devices have wide applications in many unique areas. However, the interparticle connection of photo-electrode in flexible photovoltaic devices still needs to be improved. Here, TiO{sub 2} slurries have been prepared by a three-step process, which are employed to prepare the photo-anode for flexible CuInS{sub 2} quantum dot sensitized solar cells (QDSSCs). 5 nm-sized TiO{sub 2} nanoparticles and hydrochloric acid (HCl) have been introduced in 20 nm-sized TiO{sub 2} based photo-electrodes under TiO{sub 2}/HCl mass ratio of 3:1, which exhibits excellent photovoltaic performance and charge transfer property. Due to the interparticle connection enhancement by suitable content of 5 nm-sized TiO{sub 2} nanoparticles, photo-anodes with the 20/5-TiO{sub 2} nanoparticles mass ratio of 3:1 exhibits the better optical absorption property and photovoltaic performance of flexible QDSSCs. Moreover, there has maintained 98% photovoltaic conversion efficiency of flexible QDSSCs with the seriously curving condition, which can be considered the great foreground in future applications.

14 SOLAR ENERGY↗
DOE OSTI2014

A simple dissolved metals mixing method to produce high-purity MgTiO{sub 3} nanocrystals

A simple dissolved metals mixing method has been effectively used to produce high-purity MgTiO{sub 3} (MT) nanocrystals. The method involves the mixing of independently dissolved magnesium and titanium metal powders in hydrochloric acid followed by calcination. The phase purity and nanocrystallinity were determined by making use of laboratory x-ray diffraction data, to which Rietveld-based analyses were performed. Results showed that the method yielded only one type magnesium titanate powders, i.e. MgTiO{sub 3}, with no Mg{sub 2}TiO{sub 4} or MgTi{sub 2}O{sub 5} phases. The presence of residual rutile or periclase was controlled by adding excessive Mg up to 5% (mol) in the stoichiometric mixing. The method also resulted in MT nanocrystals with estimated average crystallite size of 76±2 nm after calcination at 600°C and 150±4 nm (at 800°C). A transmission electron micrograph confirmed the formation of the nanocrystallites.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Heteropolytungstate nanoparticles: Microemulsion-mediated preparation and investigation of their catalytic activity in the epoxidation of olefins

Highlights: • Keggin type Q{sub 3}PW{sub 12}O{sub 40} nanoparticles were synthesized by using microemulsion system. • The nanoparticles have uniform size of about 25 nm and spherical morphologies. • The prepared nanoparticles act as reusable catalyst in the epoxidation of olefins with H{sub 2}O{sub 2}. - Abstract: Keggin type Q{sub 3}PW{sub 12}O{sub 40} nanoparticles (Q = cetyltrimethylammonium cation) were synthesized in water-in-oil (w/o) microemulsion consisted of water/cetyltrimethylammonium bromide/n-butanol/isooctane. Reaction of Na{sub 2}WO{sub 4}, Na{sub 2}HPO{sub 4} and hydrochloric acid within water containing nanoreactors of reverse micelles resulted in the preparation of Q{sub 3}PW{sub 12}O{sub 40} nanoparticles. The resultant nanoparticles were analyzed by physicochemical methods such as FT-IR spectroscopy, X-ray diffraction, energy-dispersive X-ray analysis, thermogravimetric analyses (TGA-DTA), scanning and transmission electron microscopy and atomic force microscopy which show nearly uniform spherical nanoparticles with size of about 15 nm. Finally, catalytic activity of the Q{sub 3}PW{sub 12}O{sub 40} nanoparticles was examined in the epoxidation of olefins with H{sub 2}O{sub 2}. The prepared nanoparticles acted as recoverable and reusable catalyst in the epoxidation of olefins with H{sub 2}O{sub 2}.

36 MATERIALS SCIENCE↗
DOE OSTI2012

Novel microwave assisted sol–gel synthesis (MW-SGS) and electrochromic performance of petal like h-WO{sub 3} thin films

Graphical abstract: Electrochromic intercalation and deintercalation of Li{sup +} ions and electrons is facilitated by providing hexagonal tunnel, trigonal cavity and square window which allows easy and fast insertion and extraction of ions. Highlights: ► Novel two step MW-SGS is first time employed to prepare WO{sub 3} thin films. ► MW-SGS is simple and cost effective technique for preparation of nanostructures. ► Petal-like hexagonal WO{sub 3} nanodisks were successfully deposited. ► O/W ratio calculated by XPS studies is 2.89. ► Good electrochromic performance suggests practical usability of proposed technique. -- Abstract: Use of domestic microwave oven is first time employed for chemical deposition of nanocrystalline hexagonal WO{sub 3} (h-WO{sub 3}) thin films. Low cost precursors like sodium tungstate, hydrochloric acid, oxalic acid and potassium sulfate signifies cost effectiveness of this thin film fabrication route. Scanning electron microscopy images reveal formation of petal like nanodisks. A number of analytical techniques were used to characterize the WO{sub 3} petal like nanodisks, including X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy, FT-IR spectroscopy, Raman scattering spectroscopy, UV–visible spectrophotometry and cyclic voltammetry (CV). The X-ray photoelectron spectroscopic studies revealed 2.89 O/W atomic ratio. The electrical transport studies on WO{sub 3} thin films show semiconducting behavior with n-type semiconductivity. The value of determined coloration efficiency is 57.90 cm{sup 2}/C. The mechanism of Li{sup +} intercalation and deinercalation in h-WO{sub 3} matrix is proposed for enhanced electrochromism.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Extraction of high value added gelatin biopolymer from black tilapia (Oreochromis mossambicus) head bones

Black tilapia (Oreochromis mossambicus) fish head bones were evaluated for its possibilities in extracting gelatin. Head bones were subjected to pre-treatment with 3% of hydrochloric acid (HCl) for demineralization before undergoes thermal extraction process. The raw head bones were characterized via Scanning Electron Microscopy (SEM) in order to investigate the external and internal surface morphology. SEM images also reveal the presence of collagen fiber with 1 µm diameter in the head bone. The black tilapia fish head bones yields 5.75 % of gelatin in wet weight basis, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw head bones and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The head bones gelatin shows high protein (10.55%) and ash (3.11 %) content with low moisture. This further proves the effectiveness of demineralization and extraction method used. The black tilapia fish head bones are found to be a prospective source of gelatin with good chemical and functional properties.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm{sup −1} and 3300 cm{sup −1} respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10{sup −2} S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

A simple route to disperse silver nanoparticles on the surfaces of silica nanofibers with excellent photocatalytic properties

Graphical abstract: The SiO{sub 2}/Ag composite nanofibers have been prepared by electrospinning and thermal decomposition of hybrid nanofibers, which exhibit a good catalytic property in reducing the methyl orange dye. Highlights: ► Hydrochloric acid was used as the catalyst of tetraethyl orthosilicate. ► Silver nanoparticles are obtained by pyrolysis of silver chloride. ► PVP–silica hybrid can disperse silver chloride and thus preventing the aggregation of silver nanoparticles. ► The catalytic activity of SiO{sub 2}/Ag composite nanofibers is much larger than that of SiO{sub 2} nanofibers. -- Abstract: In this work, monodispersed silver nanoparticles decorated SiO{sub 2} nanofibers were synthesized by electrospinning method, followed by thermal treatment at 600 °C. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermo-gravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) were used to characterize the composite nanofibers. Accordingly, the detailed formation mechanism of SiO{sub 2}/Ag composite nanofibers was discussed. Furthermore, an excellent catalytic activity of SiO{sub 2}/Ag composite fibers was observed by a degradation reaction of methyl orange (MO) dye.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Synthesis of nano-sized ZnO particles by co-precipitation method with variation of heating time

Zinc oxide powders have been synthesized by a co-precipitation method at low temperature (85 °C), using zinc acetate dihydrate, ammonia, hydrochloric acid solutions as the reactants. A number of process parameters such as reaction temperature, solution basicity or pH and heating time are the main factors affecting the morphology and physical properties of the ZnO nanostructures. In this work the effect of heating time on the morphology and particles size were studied. The as-synthesized ZnO powders were characterized using transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. The samples were also analyzed using Fourier transform infrared (FTIR). Rietveld refinement of XRD data confirms that ZnO crystallizes in the hexagonal wurtzite structure with high degree of purity and the (101) plane predominant. The XRD results show that the average crystallite sizes were about 66, 27 and 12 nm for 3, 4 and 5 h of heating times, respectively. The XRD analysis indicated that a fraction of nano-sized ZnO powders were in the form of aggregates, which was also verified by TEM image. The TEM photograph demonstrated that the nano-sized ZnO particles were a pseudo-spherical shape.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Soybean Oil Modified Bio-based Poly(vinyl alcohol)s via Ring-Opening Polymerization

In this paper, a simple method to modify the poly(vinyl alcohol) (PVA) through ring-opening reaction of epoxidized soybean oil (ESBO), catalyzed by hydrochloric acid is reported. The effect of ESBO loading ratio, in terms of mole (PVA/ESBO (n/n) = 1:0.5; 1:1 and 1:1.5) in the reaction medium, on the biodegradable, wettability and thermal properties of final PVA-SBO films is systematically investigated, comparing with PVA. The formation of PVA-SBOs is structurally confirmed by Fourier transform infrared (FT-IR) spectroscopy, whereas their wettability and thermal properties are studied by water contact angle (WCA) measurement, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC), respectively. The obtained PVA-SBOs with higher ESBO loading exhibit both improved thermal properties and higher hydrophobic characteristic compared to others. Furthermore, biodegradability of resulting PVA-SBOs is also investigated by enzymatic degradation experiments. It is determined that around 34% of PVA is degraded by enzymatic experiments after 30 days and PVA-SBO with lower ESBO loading is more degraded than others with around 52%. Consequently, some experimental results are presented to indicate that PVA-SBOs are encouraging materials for diverse applications and their extensions can be good candidate for reducing the environmental problem and consumption of petroleum resources.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Fabrication of superhydrophobic Pt{sub 3}Fe/Fe surface for its application

Well-defined Pt{sub 3}Fe/Fe superhydrophobic materials on iron sheet with special properties, such as corrosion resistance, superhydrophobicity and superoleophilicity, was fabricated. The fabrication process involved etching in hydrochloric acid aqueous solution and simple replacement deposition process without using any seed and organic solvent, and then annealing. The electrochemical measurements show that the resultant surface in 3.5% sodium chloride solution displays good corrosion resistance. Also, it is proved that the obtained surface has better mechanical abrasion resistance via scratch test. The superoleophilicity and low water adhesion force of the obtained surface endow it high oil/water separation capacity. The as-prepared nanocomposites display enhanced catalytic activity and kinetics toward degradation of methyl orange. In particular, it possesses the most efficient degradation capacity (95%) towards methyl orange at a high concentration (17.5 mg/L) in 80 min. The improved stability and excellent catalytic activity of the Pt{sub 3}Fe/Fe nanocomposites promise new opportunities for the development of waste water treatment. - Graphical abstract: The illustration of application of superhydrophobic Pt{sub 3}Fe/Fe surface Display Omitted - Highlights: • Superhydrophobic Pt{sub 3}Fe/Fe composed was fabricated on iron sheet. • The growth process is without using any seed and organic solvent. • Superhydrophobic Pt{sub 3}Fe/Fe composed show superior oil/water separation capacity. • Superhydrophobic Pt{sub 3}Fe/Fe composed show high photocatalytic activity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Leaching of Au, Ag, and Pd from waste printed circuit boards of mobile phone by iodide lixiviant after supercritical water pre-treatment

Highlights: • We report a novel process for recovering Au, Ag, and Pd from waste PCBs. • The effect of SCWO on the leaching of Au, Ag, and Pd in waste PCBs was studied. • SCWO was highly efficient for enhancing the leaching of Au, Ag, and Pd. • The optimum leaching parameters for Au, Ag, and Pd in iodine–iodide were studied. - Abstract: Precious metals are the most attractive resources in waste printed circuit boards (PCBs) of mobile phones. In this work, an alternative process for recovering Au, Ag, and Pd from waste PCBs of mobile phones by supercritical water oxidation (SCWO) pre-treatment combined with iodine–iodide leaching process was developed. In the process, the waste PCBs of mobile phones were pre-treated in supercritical water, then a diluted hydrochloric acid leaching (HL) process was used to recovery the Cu, whose leaching efficiency was approximately 100%, finally the resulting residue was subjected to the iodine–iodide leaching process for recovering the Au, Ag, and Pd. Experimental results indicated that SCWO pre-treatment temperature, time, and pressure had significant influence on the Au, Ag, and Pd leaching from (SCWO + HL)-treated waste PCBs. The optimal SCWO pre-treatment conditions were 420 °C and 60 min for Au and Pd, and 410 °C and 30 min for Ag. The optimum dissolution parameters for Au, Pd, and Ag in (SCWO + HL)-treated PCBs with iodine–iodide system were leaching time of 120 min (90 min for Ag), iodine/iodide mole ratio of 1:5 (1:6 for Ag), solid-to-liquid ratio (S/L) of 1:10 g/mL (1:8 g/mL for Ag), and pH of 9, respectively. It is believed that the process developed in this study is environment friendly for the recovery of Au, Ag, and Pd from waste PCBs of mobile phones by SCWO pre-treatment combined with iodine–iodide leaching process.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Recycling Isotopically Enriched Mo from the RadioGenix Waste Stream

NorthStar’s RadioGenix generator utilizes an aqueous biphasic extraction chromatography column to separate Tc from low-specific-activity 99 Mo. During this separation process, a fraction of the source Mo material can be found in the waste. This is not of concern when natural Mo targets are used. However, the introduction of isotopically enriched 98 Mo for neutron capture or 100 Mo for accelerator-based production requires recovery of this valuable enriched Mo material. The generator waste is absorbed and solidified in a superabsorbent hydrogel polymer. In this contribution, we report results from our small-scale experimental study on development of a separation process for recovery of molybdenum from the polymeric gel waste using common chemicals and simple chemical techniques. Our investigation confirms that the acidic deswelling of the alkaline hydrogel with concentrated hydrochloric acid converts the occluded molybdate to a neutral molybdenyl dichloride species that is freely released from the gel. Mo can then be concentrated on a commercial tri-n-butyl phosphate resin, eluted with ammonium hydroxide, and crystallized as ammonium heptamolybdate for conversion back to Mo metal. Typical Mo recoveries are 90-95%.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

Understanding Aqueous Electrolyte Stability through Combined Computational and Magnetic Resonance Spectroscopy: A Case Study on Vanadium Redox Flow Battery Electrolytes

Redox flow battery (RFB) is a promising candidate for energy storage component in designing resilient grid scale power supply due to the advantage of the separation of power and energy. However, poorly understood chemical and thermal stability issues of electrolytes currently limit the performance of RFB. Designing of high performance stable electrolytes requires comprehensive knowledge about the molecular level solvation structure and dynamics of their redox active species. The molecular level understanding of detrimental V2O5 precipitation process led to successful designing of mixed acid based electrolytes for vanadium redox flow batteries (VRFB). The higher stability of mixed acid based electrolytes is attributed to the choice of hydrochloric acid as optimal co-solvent, which provides chloride anions for ligand exchange process in vanadium solvation structure. The role of chloride counter anion on solvation structure and dynamics of vanadium species were studied using combined magnetic resonance spectroscopy and DFT based theoretical methods. Finally, the solvation phenomenon of multiple vanadium species and their impact on VRFB electrolyte chemical stability were discussed.

Comprehensive Solvation Chemistry↗
NASA NTRS1988

On the growth of nitric and sulfuric acid aerosol particles under stratospheric conditions

A theory for the formation of frozen aerosol particles in the Antarctic stratosphere was developed and applied to the formation of polar stratospheric clouds. The theory suggests that the condensed ice particles are composed primarily of nitric acid and water, with small admixtures of sulfuric and hydrochloric acids in solid solution. The proposed particle formation mechanism is in agreement with the magnitude and seasonal behavior of the optical extinction observed in the winter polar stratosphere.

Hamill, Patrick↗
DOE OSTI2017

A Combined Density Functional Theory and Spectrophotometry Study of the Bonding Interactions of [NpO 2 ·M] 4+ Cation–Cation Complexes

The equilibrium constants for [NpO 2 M∙] 4+ (M = Al 3+ , In 3+ , Sc 3+ , Fe 3+ ) in μ = 10 M nitric acid and [NpO 2 ∙Ga] 4+ in μ = 10 M hydrochloric acid media have been determined. The trend in the interaction strength follows: Fe 3+ > Sc 3+ In 3+ > Ga 3+ Al 3+ . These equilibrium constants are compared to those of previously reported values for NpO 2 + complexes with Cr 3+ and Rh 3+ within the literature. Thermodynamic parameters and bonding modes are discussed, with density functional theory and natural bond orbital analysis indicating that the NpO 2 + dioxocation acts as a -donor with transition-metal cations and a sigma donor with group 13 cations. The small changes in electron-donating ability is modulated by the overlap with the coordinating metal ion's valence atomic orbitals.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Microwave-Mediated Extraction of Critical Metals from LED E-Waste

This study introduces a microwave-assisted technique for extracting critical minerals from LED electronic waste. The process begins with microwave irradiation, which thermally decomposes the LED’s plastic lens into a brittle, charred residue. During this stage, the LED chip undergoes deflagration—being rapidly ejected from the reflective cavity and becoming embedded within the decomposed lens material. Consequently, the chip is encapsulated in the resulting charred residue. This composite, consisting of the charred lens and the LED chip, can be easily separated from the metallic pins (Fe, Ni, Ag), which remain almost undamaged. Subsequent calcination of the charred material in air exposes the materials making up the LED chip, which contain critical metals (e.g., Ga, As, In, Y, Au). These metals are then extracted through a two-step acid leaching process involving aqua regia followed by hot concentrated hydrochloric acid, yielding them in potentially recoverable forms. The synergistic effect of microwave irradiation and acid treatment achieves an average extraction efficiency of 96% for critical metals. Notably, this approach enables complete and loss-free recovery of the LED chip, offering a practical and efficient solution for LED e-waste recycling.

Bourlinos, Athanasios B.↗
DOE OSTI2022

Rare earth element separations by high-speed counter-current chromatography

We report that following the initial development of High-Speed Counter-Current Chromatography (HSCCC) in the 1960s, several studies have explored its applicability in the separation of rare earth elements (REEs). More recently, however, HSCCC publications have transitioned towards the separation of natural products or pharmaceuticals, leaving the application for REEs largely unexplored from a practical standpoint. Herein, we expand upon prior work in this field by evaluating the suitability of HSCCC to separation of a subset of non-radioactive REEs (Nd, Sm, Eu, Tb, and Y) at 10 -4 mol levels using di-(2-ethylhexyl)phosphoric acid (HDEHP) in n-heptane as the stationary phase and hydrochloric acid as the mobile phase. First, the effect of flow rate on the stationary phase volume retention ratio and resolution of Nd/Sm/Eu subgroup was evaluated followed by optimization of step-gradient elution profiles resulting in additional recovery of Tb and Y within a seven-hour window. The five REEs were separated at the baseline resolution level or above. Elution profiles obtained from multiple runs across two independently operated columns and across independent runs were cross analyzed. Reproducibility in elution profiles point to future applications in radioelement separation chemistry, where both chemical and radiochemical purity are of importance.

47 OTHER INSTRUMENTATION↗