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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 631 records · Page 35
All sourcesNASA NTRSDOE OSTI
NASA NTRS2014

Active Flow Separation Control on a NACA 0015 Wing Using Fluidic Actuators

Results are presented from a recent set of wind tunnel experiments using sweeping jet actuators to control ow separation on the 30% chord trailing edge ap of a 30 deg. swept wing model with an aspect ratio (AR) of 4.35. Two sweeping jet actuator locations were examined, one on the flap shoulder and one on the trailing edge flap. The parameters that were varied included actuator momentum, freestream velocity, and trailing edge flap deflection (Delta f ) angle. The primary focus of this set of experiments was to determine the mass flow and momentum requirements for controlling separation on the flap, especially at large flap deflection angles which would be characteristic of a high lift system. Surface pressure data, force and moment data, and stereoscopic particle image velocimetry (PIV) data were acquired to evaluate the performance benefits due to applying active flow control. Improvements in lift over the majority of the wing span were obtained using sweeping jet actuator control. High momentum coefficient, Cu, levels were needed when using the actuators on the ap because they were located downstream of separation. Actuators on the flap shoulder performed slightly better but actuator size, orientation, and spacing still need to be optimized.

Melton, Latunia P.↗
DOE OSTI2017

Solid Secondary Waste Form Testing Activities for the Integrated Disposal Facility Performance Assessment Support - 17567

Solid secondary waste (SSW) that will be generated at the Waste Treatment and Immobilization Plant (WTP) and from other activities at the Hanford site is destined for disposal at the Integrated Disposal Facility (IDF). Construction of the IDF was undertaken based on a Performance Assessment (PA) performed in 2001. In 2016, a SSW data package was prepared to support the development of an updated PA (2017 IDF PA). There are many inputs required to support the IDF PA. Data needs were identified based on experience from the previous PAs and from the development of conceptual models and modeling approaches to be applied for the 2017 PA. Interactions with the IDF PA team and the inventory data package developer helped to focus detailed efforts on a few key waste streams, contaminants of concern, and disposal configurations that are expected to be the primary contributors to the dose resulting from SSW disposed at the IDF. The key waste streams include: High Efficiency Particulate Air (HEPA) filters, ion exchange resins, granular activated carbon, and Ag-mordenite. The key parameters addressed in the 2016 data package include: saturated hydraulic conductivity, moisture characteristic curves, effective diffusion coefficient, distribution coefficient and porosity. The IDF PA team also identified a set of key contaminants that are expected to be the primary concern for the PA calculations (Tc-99, I-129, Cs-137, Sr-90, uranium isotopes (and total uranium), chromium, mercury and nitrate). These contaminants were the focus of the SSW data package. Specific formulations had not been identified for cementitious materials that will be used to encapsulate or stabilize SSW, and no IDF-specific experiments had been conducted to obtain the data for the PA. Thus, for the 2016 SSW data package, recommended property values were provided for a range of representative candidate materials based on a review of existing literature. However, starting in FY17, IDF-specific experiments will be performed for Hanford SSW expected to contribute most significantly to the dose for the IDF. This paper will summarize the information obtained for the 2016 data package and the plans for further testing to refine key inputs for the IDF PA. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Wear and Corrosion Resistances of Active Screen Plasma-Nitrided Duplex Stainless Steels

Two grades of duplex stainless steel, SAF 2205 and SAF 2507, were nitrided using an active screen plasma process carried out at 380 °C for 10 h and were characterized in terms of microstructure and hardness. Wear resistance was assessed by means of linear scratch tests, using loads below and above the critical load. Potentiodynamic polarization was used to analyze corrosion behavior in 0.6 M NaCl solution. X-ray diffractometry showed expanded austenite formation in all nitrided samples. The super duplex steel SAF 2507 showed much better scratch resistance, with low friction coefficient and greater toughness, as judged by the pattern of superficial cracks when it was tested above the critical load. The corrosion behavior of steels was also different, mainly in the active region, and nitriding had a more beneficial effect upon SAF 2507. The potential relative to the transpassive region was practically unaffected by the nitriding.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Decoding the protein–ligand interactions using parallel graph neural networks

Abstract Protein–ligand interactions (PLIs) are essential for biochemical functionality and their identification is crucial for estimating biophysical properties for rational therapeutic design. Currently, experimental characterization of these properties is the most accurate method, however, this is very time-consuming and labor-intensive. A number of computational methods have been developed in this context but most of the existing PLI prediction heavily depends on 2D protein sequence data. Here, we present a novel parallel graph neural network (GNN) to integrate knowledge representation and reasoning for PLI prediction to perform deep learning guided by expert knowledge and informed by 3D structural data. We develop two distinct GNN architectures: $$\hbox {GNN}_{\mathrm{F}}$$ GNN F is the base implementation that employs distinct featurization to enhance domain-awareness, while $$\hbox {GNN}_{\mathrm{P}}$$ GNN P is a novel implementation that can predict with no prior knowledge of the intermolecular interactions. The comprehensive evaluation demonstrated that GNN can successfully capture the binary interactions between ligand and protein’s 3D structure with 0.979 test accuracy for $$\hbox {GNN}_{\mathrm{F}}$$ GNN F and 0.958 for $$\hbox {GNN}_{\mathrm{P}}$$ GNN P for predicting activity of a protein–ligand complex. These models are further adapted for regression tasks to predict experimental binding affinities and $$\hbox {pIC}_{\mathrm{50}}$$ pIC 50 crucial for compound’s potency and efficacy. We achieve a Pearson correlation coefficient of 0.66 and 0.65 on experimental affinity and 0.50 and 0.51 on $$\hbox {pIC}_{\mathrm{50}}$$ pIC 50 with $$\hbox {GNN}_{\mathrm{F}}$$ GNN F and $$\hbox {GNN}_{\mathrm{P}}$$ GNN P , respectively, outperforming similar 2D sequence based models. Our method can serve as an interpretable and explainable artificial intelligence (AI) tool for predicted activity, potency, and biophysical properties of lead candidates. To this end, we show the utility of $$\hbox {GNN}_{\mathrm{P}}$$ GNN P on SARS-Cov-2 protein targets by screening a large compound library and comparing the prediction with the experimentally measured data.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Self‐Lubricating Tribo‐Catalytic Activity of 2D High Entropy Alloy Nanoflakes

High Entropy Alloys (HEAs) have garnered attention due to their remarkable tribological attributes. Predominantly, failure mechanisms in HEAs emanate from stress‐induced dislocations, culminating in crack propagation and film delamination. In this study, we report on the synthesis of 2D HEA of (MoWNbTaV) 0.2 S 2 which facilitates shear‐induced energy dissipation at sliding interfaces. The ball‐on‐disk tribological investigations demonstrate unprecedentedly low average coefficients of friction (0.076) and wear rates (10 −9 mm 3 (N∙m) −1 ) under high contact pressures (0.936 GPa) within ambient conditions. Employing multi‐scale characterizations alongside molecular dynamic simulations, we elucidate that the presence of the HEA triggers tribocatalytic activity under high contact pressures emerging as a pivotal factor in extending lubricant lifespan during tribological tests. The resilient lubriciousness coupled with the facile spray coating methodology of (MoWNbTaV) 0.2 S 2 in ambient environments paves the way for the development of a new class of solid lubricants based on 2D HEA.

2D solid lubricant↗
DOE OSTI2019

Viscosities, diffusion coefficients, and mixing times of intrinsic fluorescent organic molecules in brown limonene secondary organic aerosol and tests of the Stokes–Einstein equation

Viscosities and diffusion rates of organics within secondary organic aerosol (SOA) remain uncertain. Using the bead-mobility technique, we measured viscosities as a function of water activity ( a w ) of SOA generated by the ozonolysis of limonene followed by browning by exposure to NH 3 (referred to as brown limonene SOA or brown LSOA). These measurements together with viscosity measurements reported in the literature show that the viscosity of brown LSOA increases by 3–5 orders of magnitude as the a w decreases from 0.9 to approximately 0.05. In addition, we measured diffusion coefficients of intrinsic fluorescent organic molecules within brown LSOA matrices using rectangular area fluorescence recovery after photobleaching. Based on the diffusion measurements, as the a w decreases from 0.9 to 0.33, the average diffusion coefficient of the intrinsic fluorescent organic molecules decreases from 5.5 × 10 - 9 to 7.1 × 10 - 13 cm 2 s -1 and the mixing times of intrinsic fluorescent organic molecules within 200 nm brown LSOA particles increases from 0.002 to 14 s. These results suggest that the mixing times of large organics in the brown LSOA studied here are short ( < 1 h) for a w and temperatures often found in the planetary boundary layer (PBL). Since the diffusion coefficients and mixing times reported here correspond to SOA generated using a high mass loading ( ~1000 µ g m -3 ), biogenic SOA particles found in the atmosphere with mass loadings ≤10 µ g m -3 are likely to have higher viscosities and longer mixing times (possibly 3 orders of magnitude longer). These new measurements of viscosity and diffusion were used to test the accuracy of the Stokes–Einstein relation for predicting diffusion rates of organics within brown LSOA matrices. The results show that the Stokes–Einstein equation gives accurate predictions of diffusion coefficients of large organics within brown LSOA matrices when the viscosity of the matrix is as high as 10 2 to 10 4 Pa s. These results have important implications for predicting diffusion and mixing within SOA particles in the atmosphere.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1985

Magnetospheric impulse response for many levels of geomagnetic activity

The temporal relationship between the solar wind and magnetospheric activity has been studied using 34 intervals of high time resolution IMP 8 solar wind data and the corresponding AL auroral activity index. The median values of the AL index for each interval were utilized to rank the intervals according to geomagnetic activity level. The linear prediction filtering technique was then applied to model magnetospheric response as measured by the AL index to the solar wind input function VB(s). The linear prediction filtering routine produces a filter of time-lagged response coefficients which estimates the most general linear relationship between the chosen input and output parameters of the magnetospheric system. It is found that the filters are composed of two response pulses speaking at time lags of 20 and 60 min. The amplitude of the 60-min pulse is the larger for moderate activity levels, while the 20-min pulse is the larger for strong activity levels. A possible interpretation is that the 20-min pulse represents magnetospheric activity driven directly by solar wind coupling and that the 60-min pulse represents magnetospheric activity driven by the release of energy previously stored in the magnetotail. If this interpretation is correct, the linear filtering results suggest that both the driven and the unloading models of magnetospheric response are important facets of a more comprehensive response model.

Bargatze, L. F.↗
DOE OSTI2019

Evaluation of Superconducting Properties and Diffusion Behavior of Ex Situ and In Situ Bulk MgB{sub 2} Materials with Ni Coating

Ex situ and in situ bulk MgB{sub 2} superconducting materials have successfully been produced by the simple amorphous boron and nano-amorphous boron powders with the processes of ball milling, pressing, and annealing. The superconducting properties and diffusion behavior of MgB{sub 2} samples after nickel (Ni) coating process have been characterized and compared to the microstructure and performance of uncoated (bare) MgB{sub 2} bulk sample. One surface of MgB{sub 2} superconductor sample was coated with a thin Ni layer of about 50 − 60μm thickness using vapor deposition techniques in versatile high vacuum coater, then every sample was annealed at temperatures between 923 and 1123 K for 1 h. The role of annealing temperature on physical, electrical, superconducting, and structural characterizations of bare and Ni-coated ex situ/in situ MgB{sub 2} bulk superconductors has been studied using X-ray diffraction and dc electrical resistivity versus temperature measurements. Finally, the Ni diffusion coefficients (D{sub Ni} = D{sub 0}exp(E/k{sub B}T)) are calculated in the temperature range to calculate the required minimum activation energy value for the Ni atoms/ions into the ex situ MgB{sub 2} crystal structure for the first time.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
NASA NTRS1981

The atmosphere and ionosphere of Jupiter

The thermal structure of the upper atmosphere of Jupiter, the composition of the atmosphere and the strength of mechanical mixing, and sources and sinks of ionization in the Jupiter ionosphere are described from Voyager UV spectrometer, radio, IR, and imaging data. A topside ionospheric temperature of 1300 K was observed, along with an energy equilibrium between the plasma and neutral gas in the upper atmosphere. A composite thermal structure is provided, noting a close similarity to earth conditions at upper levels, and enhanced thermal behavior has been detected between the times of solar minimum and maximum activity. Ammonia photochemistry is examined, and measured concentrations of H2, CH4, C2H6, and C2H2 as a function of height are outlined. Eddy diffusion coefficient calculations are carried out, yielding a highest Ly-alpha intensity of 100 million sq cm/sec. The increased exospheric temperature between 1973 and 1980 is stressed to have no known satisfactory explanation.

Atreya, S. K.↗
NASA NTRS1996

Experimental Optimization Methods for Multi-Element Airfoils

A modern three element airfoil model with a remotely activated flap was used to investigate optimum flap testing position using an automated optimization algorithm in wind tunnel tests. Detailed results for lift coefficient versus flap vertical and horizontal position are presented for two angles of attack: 8 and 14 degrees. An on-line first order optimizer is demonstrated which automatically seeks the optimum lift as a function of flap position. Future work with off-line optimization techniques is introduced and aerodynamic hysteresis effects due to flap movement with flow on are discussed.

Landman, Drew↗
NASA NTRS1973

Microwave emission and scattering from vegetated terrain

Models are developed for the apparent temperature and backscattering coefficient of vegetated terrain to illustrate the effects of vegetation on the sensitivity of these parameters to variations of soil moisture. Three types of terrain are simulated for both the passive and the active case: a uniform canopy over a smooth surface, plant rows on a smooth surface, and plant rows on a rough surface. In each case the canopy is defined by its overall dimensions and by its electric permittivity, which is determined from Weiner model for dielectric mixture. Emission and scattering from both the soil and the canopy are considered, but atmospheric effects are neglected. Calculated data indicate that the sensitivity of the apparent temperature and backscattering coefficient to variations of soil moisture, decreases as the amount of vegetation increases. It is shown that the same effect results from increasing signal frequency or angle of incidence.

Sibley, T. G.↗
DOE OSTI2021

Identification and quantification of distinct active sites in Hf-Beta zeolites for transfer hydrogenation catalysis

Despite the significant progress made in characterizing different framework heteroatom sites that exist in Lewis acidic zeolites with probe molecule adsorption and spectroscopy, methods to reliably quantify site counts remain indefinite and have been primarily limited to Sn and Ti Lewis acid sites. Here, methods to quantify framework Lewis acidic Hf 4+ sites in zeolite Beta (Hf-Beta) with two Lewis base titrants (pyridine, deuterated acetonitrile) were developed using infrared (IR) spectroscopy. Lewis acid site counts for Hf-Beta zeolites were validated by measuring integrated molar extinction coefficients (IMECs; ε, cm μmol –1 ) on Sn-Beta zeolites using identical Lewis base titrants to benchmark site counts with established literature procedures to quantify Lewis acid sites in Beta zeolites from IR spectra. Highlighting the importance of benchmarking active site counts against well-established experimental protocols, IMECs of CD 3 CN bound to open (ε(Sn; 2316 cm –1 ): 1.80 ± 0.25) and closed (ε(Sn; 2308 cm –1 ): 3.76 ± 0.33) Sn sites were ~1.8x larger than those previously reported while total Lewis acid site counts agreed with those measured by pyridine (ε(Sn; 1451 cm –1 ): 1.58 ± 0.16) on six different Sn-Beta zeolites. IMECs measured for IR peaks reflecting pyridine bound to Lewis acidic Hf sites (ε(Hf; 1448 cm –1 ): 1.54 ± 0.21) and CD 3 CN bound to open (ε(Hf; 2313 cm –1 ): 2.40 ± 0.22) and closed (ε(Hf; 2307 cm –1 ): 3.55 ± 0.41) Hf sites, gave similar counts for the total number of Lewis acidic sites across six Hf-Beta zeolites (Si/Hf = 100–413). Consistent with previous reports with Sn-Beta catalysts where open Sn sites are responsible for catalytic turnover, apparent first and zero-order MPVO rate constants (0.01–1 M cyclohexanone in 2-butanol; per total Hf, 373 K) correlated with the total number of open Hf sites, per total Hf, but not with the total number of closed Hf sites or total Lewis acid site counts. Measured initial MPVO rates (0.1 M cyclohexanone in 2-butanol, per open Hf, 373 K) were ~25x higher on hydrophobic Hf-Beta-F than on hydrophilic Hf-Beta-OH zeolites. Overall, the apparent first-order MPVO rate constants (2-butanol solvent, per open Hf, 373 K) were ~6x higher on Hf-Beta-F than on Hf-Beta-OH zeolites. The characterization methods reported here enable normalization of MPVO turnover rates on Sn- and Hf-Beta zeolites by their number of open sites. Finally, this enables performing quantitative rate comparisons across Lewis acid zeolites of varying active site identity, solvation, and pore topology used in liquid-phase catalysis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1990

Interplanetary Alfven waves and auroral (substorm) activity - IMP 8

Almost 1 year of IMP 8 interplanetary magnetic field and plasma data (days 1-312, 1979) have been examined to determine the interplanetary causes of geomagnetic AE activity. The nature of the interplanetary medium (Alfvenic or non-Alfvenic) and the B(s) correlation with AE were examined over 12-hour increments throughout the study. It is found that Alfvenic wave intervals are present over 60 percent of the time, and the southward component of the Alfven waves is well correlated with AE (average peak correlation coefficient 0.62), with a median lag of 43 min. From this statistical study, no major differences in the magnetospheric response to Alfvenic and non-Alfvenic intervals were obvious. The high-intensity long-duration continuous AE activity (HILDCAA) events discussed previously by Tsurutani and Gonzales (1987) are demonstrated to be caused by the southward components of the Alfven waves, presumably through the process of magnetic reconnection.

Tsurutani, Bruce T.↗
DOE OSTI2021

Kinetic Measurements in Heterogeneous Catalysis

This contribution is about the experimental determination of the rate of a heterogeneous catalytic reaction and the analysis of kinetic data. In this case, the reaction rate can be defined as the frequency at which the closed sequence of elementary steps transforming reactants into products is occurring. However, the rate of chemical reaction is not directly observed; rather, one records the rate of substance change. The rate of chemical reaction is calculated based on the rate of substance change and assumed stoichiometry of the reaction. In order to make this an intensive quantity (i.e., independent of the volume in which the reaction is performed, this frequency is divided by the latter or by a quantity proportional to the latter). As the focus of what follows is on heterogeneously catalyzed reactions this can be the catalyst mass, the catalyst surface area or the total number of active sites present in the reaction volume confined by the walls of a chemical reactor. For example, the rate may be reported as one of the following: Net rate of consumption/production of component i mol m-3 s-1 Net specific rate of consumption/production of component i mol kg-1 s-1 Rate of substance change (per unit volume of catalyst) mol m-3 s-1 Specific reaction rate (per unit mass of catalyst) mol kg-1 s-1 Net rate of consumption/production of component i mol m-2 s-1 The turnover frequency (TOF) is a characteristic originally introduced by Boudart [1] is expressed as TOF=R/G_tot , where R is the steady-state rate of reactant consumption or product generation and G_totis the total areal density of active sites [mol m-2]. The latter is typically taken from experimental chemisorption data obtained at low temperature. The advancement of a chemical reaction leads to changes in the amounts of reactants and products which, for a stoichiometric single reaction, are connected by the stoichiometric coefficients. In many cases, for the sake of simplicity, we will assume that the investigated reaction proceeds according to a single reaction pathway, so that the net production rate of a reaction component is directly proportional to the reaction rate and that the latter equals the net production rate of any of the involved components when divided by the appropriate stoichiometric coefficient. For complex stoichiometric reactions the net production rates of the involved components are linear combinations of the reaction rates. Different goals for kinetic measurements can be formulated: Catalyst testing, i.e., obtaining the kinetic dependences for the development and discrimination of efficient catalytic materials. Precise kinetic characterization of active materials via high-throughput screening is a part of such activity. Detailed kinetics, i.e., revealing the detailed mechanism of complex catalytic reaction via systematic kinetic studies, both steady-state and non-steady-state Industrial kinetics, i.e., obtaining data and relationships for describing and predicting the behaviour of catalytic reactors and processes at industrial scale Finally, mathematical modeling and analysis where kinetic measurements provide data for understanding complex kinetic phenomena, e.g., oscillations, non-linear self-organization, etc.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Characterization of the pyroelectric coefficient of a high-temperature sensor

Temperature is one of the most important thermodynamic properties measured and controlled in energy generation systems. To operate the energy system at optimum operating conditions for lower emission and higher efficiency, it is important to measure real-time temperatures. Furthermore, temperature sensing in intense environments is necessary since most sensors in energy systems get exposed to elevated temperatures, corrosive environments, and elevated pressures. One of the solutions for developing harsh environment sensors is to use ceramic materials, especially functional ceramics such as pyroelectrics. Pyroelectric ceramics could be used to develop active sensors for both temperature and pressure due to their capabilities in coupling energy among mechanical, thermal, and electrical domains. In this study, Lithium niobate (LiNbO 3 ) pyroelectric ceramic material was used to develop a temperature sensor for high-temperature applications. LiNbO 3 has high Curie temperature (1210°C) compared to other pyroelectric ceramic materials. A high Curie temperature material is important since the polarization properties of the material break down above the Curie temperature. Hence, the use of a material with a higher Curie temperature, such as LiNbO 3 , makes it promising to be used as a sensing material for high-temperature applications. A study was performed to actively measure the temperature up to 500°C using a pyroelectric ceramic lithium niobate (LiNbO 3 ) as a sensor material. Due to the non-linear pyroelectric response of LiNbO 3 , the temperature-dependent pyroelectric coefficient of LiNbO 3 was measured with a dynamic pyroelectric coefficient technique in temperature ranges up to 500°C. Temperature-dependent pyroelectric coefficient of LiNbO 3 was found to increase from −0.5 × 10 −5 to −3.70 × 10 −5 C/m 2 °C from room temperature to 500°C. The LiNbO 3 sensor was then tested for higher temperature sensing at 220°C, 280°C, 410°C, and 500°C and has shown 4.31%, 2.1%, 0.4%, and 0.6% deviation, respectively, compared with thermocouple measurements.

Sarker, Md Rashedul H.↗
DOE OSTI2018

Prominent Study on Surface Properties and Diffusion Coefficient of Urease-Conjugated Magnetite Nanoparticles

Herein, the magnetite nanoparticles (MNs) were prepared by facile solvothermal method and its porous nature was modified using 3-(2-aminoethyl)-3-aminopropyl trimethoxysilane (AEAPS). Magnetite formation, successful amino tagging, and urease conjugation on the surface were confirmed from the presence of certain functional groups in Fourier transform infrared (FT-IR) spectra. Also, nanosize (13.2 nm) and spherical morphology of MNs were evaluated from diffraction patterns and electron micrographs respectively. Lower retentivity and coercivities in magnetization curve revealed the superparamagnetic behavior, and nitrogen adsorption/desorption curves exhibited decrease in its surface porosity. Conductivity measurements showed lower diffusion coefficient (D{sub e} = 1.9 × 10{sup −17} cm{sup 2}/min) and higher diffusion with limited hydrolytic reaction in native urease and improved activity of conjugated urease with higher D{sub e} (12.62 × 10{sup −16} cm{sup 2}/min). Hence, this study revealed that the surface porous nature of MNs can be altered effectively by amino tagging in order to overcome diffusional limitations thereby enhancing enzyme activity.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2026

Structuring, stochastic behavior, and charge storage capacity of redox-active microemulsions formulated with mixtures of toluene and ionic liquid as oil phase

Oil/water microemulsions (µEs) are promising electrolytes for redox flow batteries (RFBs) as they simultaneously improve charge capacity and ionic conductivity. Here, we report the successful formulation of bicontinuous µEs where the oil phase is a solution of trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide ionic liquid in toluene with redox-active ferrocene. We examined the effect of supporting electrolyte anion (NO 3 – , Cl – , ClO 4 – ) on the structure, reactivity, transport, and electrolytic performance of redox-active µEs. Neutron scattering and nuclear magnetic resonance showed that the domain size increased as Cl – > NO 3 – > ClO 4 – while the ferrocene diffusion coefficient increased as NO 3 – > Cl – > ClO 4 – . Scanning electrochemical microscopy indicated anion-dependent current fluctuations during electrolysis, with ClO 4 – exhibiting the least high-frequency oscillations, which correlate to the highest charge and discharge capacity and reversibility. All ionic liquid containing systems improved the performance of toluene-based µEs, highlighting new design principles for these electrolytes.

diffusion↗