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Results for “synergistic effect”

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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Synergies between H, He and radiation damage in dual and triple ion irradiation of candidate fusion blanket materials

Three ferritic/martensitic alloys were studied to understand the synergistic effect between single ion beam (Fe 2+ ), dual ion beam (Fe 2+ +He 2+ and Fe 2+ +H + ), and triple ion beam (Fe 2+ +He 2+ +H + ) irradiations on cavity evolution. A commercial alloy, F82H, a castable nanostructured alloy, CNA3, and a high purity model alloy, Fe8Cr2W, were irradiated at 400°C to 600°C to a damage level of 50 dpa at a damage rate of 1 × 10 –3 dpa/s with He and H injection rates of 10 and 40 appm/dpa, respectively. Post-irradiation characterization via bright field transmission electron microscopy and high-angle annular dark-field scanning transmission electron microscopy was performed on all irradiated conditions to characterize the cavity size distribution and determine the effects of H/He injection on cavity microstructure. In all three alloys, hydrogen co-injection with helium resulted in an increased cavity number density and maximum cavity size, producing an increase in swelling over that from helium injection alone. Swelling in F82H appears to peak between 450°C and 500°C. At 600°C, swelling was minimal and cavities of high density and small size were confined to grain boundaries and dislocations while at 400°C, swelling is also low with a nearly homogeneous, high density, distribution of very small cavities throughout. Swelling was least in the commercial alloy F82H due to the high sink strength. The CNA3 alloy underwent dissolution of precipitates that lowered the sink strength and resulted in higher swelling than F82H, but less than the model alloy. Electron energy loss spectroscopy (EELS) elemental mapping revealed hydrogen forming a halo-like structure about the periphery of the cavities and helium residing within the cavities themselves. Finally, this observation suggests that hydrogen reduces the surface energy of helium-filled cavities which results in both increased cavity number density and cavity size in triple beam irradiation over dual beam irradiation.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Assessing the coating implications of slurry formulations in NCMA and LFMP blend cathodes for lithium-ion batteries

This paper investigates the implications of slurry formulations and electrode processing on the performance of lithium-ion battery (LIB) cathodes, focusing on Nickel Cobalt Manganese Aluminum (NCMA) and Lithium Ferro Manganese Phosphate (LFMP) blends. Through a comprehensive examination of electrode processing steps, from material selection to coating application, we elucidate the critical role of processing parameters in shaping electrode morphology and electrochemical behavior. Rheological studies reveal the influence of slurry composition on viscosity and flow behavior, highlighting the importance of achieving optimal rheological properties for uniform coating deposition. Electrochemical characterization, including cyclic voltammetry and rate capability tests, unveils the electrochemical behavior of NCMA, LFMP, and their blend, showcasing the synergistic effects of material blending on battery performance. In conclusion, our findings underscore the intricate relationship between slurry formulation, electrode processing, and LIB performance, offering valuable insights for the design and optimization of high-performance electrode materials for next-generation batteries.

25 ENERGY STORAGE↗
DOE OSTI2020

Robust natural nanocomposites realizing unprecedented ultrafast precise molecular separations

Synthetic polymer membranes can potentially reduce the large energy and carbon footprints that are typically associated with traditional chemical separation technologies. Unfortunately, current production protocols negate the green benefits of membrane separation. To address this bottleneck, here we report the use of natural materials monosaccharide – glucose and polydopamine and Zr-based metal organic frameworks (MOFs) to fabricate ultrathin nanocomposite membranes via interfacial polymerization reaction. The synergistic effect of these three materials on angstrom-scale molecular transport both in organic solvent and aqueous environment was elucidated using a series of complementary techniques. We demonstrate such nature-inspired nanocomposite membranes enable structural stability even in polar aprotic solvents, and unparalleled ultra-fast, low-pressure, precise separations in both nanofiltration modes, which easily surpass state-of-the-art membranes relying on unsustainable materials. Finally, the multi-functionality of saccharide nanocomposites was elegantly harnessed to impact separation applications that contribute towards a better living environment.

36 MATERIALS SCIENCE↗
DOE OSTI2021

High-performance multiblock PEMs containing a highly acidic fluorinated-hydrophilic domain for water electrolysis

The present paper describes the design and evaluation of novel hydrophilic–hydrophobic poly(arylene ether sulfone) (PAES) multiblock copolymers for their synergistic effects upon transport properties and their potential use in proton exchange membrane water electrolysis. The multiblock copolymers are prepared via a coupling reaction between (i) a hydrophilic segment consisting of a disulfonated quinone fluorinated biphenyl group that contains fluorine moieties next to the sulfonated groups to increase the acidity, and (ii) hydrophobic segments composed of non-sulfonated biphenyl sulfone to provide dimensional stability. Two different lengths (molecular weights; 5k and 10k, where k represents 10 3 g mol -1 ) of hydrophobic segments are used to investigate the effects of the membrane properties compared with those of Nafion® and PAES random copolymer (i.e., BPSH40). Atomic force microscopy images of the BPSH40 and multiblock membranes are shown to agree closely with a mesoscale simulation, thus confirming the importance of the morphological effect upon the transport properties. Furthermore, the multiblock copolymer with a higher proportion of hydrophilic segments (10 k–5k) was shown to provide enhanced performance (3.41 A cm -2 at 1.9 V) compared to the multiblock copolymer with equal proportions of hydrophilic and hydrophobic segments (10 k–10 k) due to the greater continuity of nano-sized ionic channels.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

In situ monitoring of dislocation, twinning, and detwinning modes in an extruded magnesium alloy under cyclic loading conditions

This work investigates the microscopic deformation mechanisms of an extruded, precipitation-strengthened AZ80 magnesium (Mg) alloy subjected to strain-controlled low-cycle fatigue using in situ neutron diffraction measurements. Results demonstrate that the plastic deformation during cyclic loading is dominated by the alternating {10.2} extension twinning and detwinning mechanisms. The observed deformation mode is strongly texture and precipitate dependent. For the initial texture, the tested material has two major texture components which result in the occurrence of extension twinning during both compression and reverse tension in the first two cycles. The prolonged detwinning process in the following cycles is proposed to relieve the shear stress field of {00.2} grains, leading to the disappearance of twinning. The precipitation strengthening results in an increase of the critical resolved shear stress (CRSS) by similar to 33 MPa for the extension twinning in this AZ80 alloy. Here, the synergistic effects of the initial texture, precipitation strengthening, and load sharing of various grain families and phases contribute to the complicated evolution of dominant deformation mechanisms, among which elevated dislocation activities are believed to be responsible for the relatively poor low-cycle-fatigue lifetime when compared to other Mg alloys.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Highly thermally stable copolymers of epoxy and trifunctional polybenzoxazine

Here, in this work, we report the copolymerization of a triamine-based benzoxazine and a commercial difunctional epoxy resin, and investigate their synergistic effect on improved thermal properties using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Results showed that a glass transition temperature increase of up to 268 °C was obtained for the copolymer with as low as 25 wt% epoxy. A higher thermal performance was also achieved with an onset degradation of nearly 400 °C and char yield of 39 wt% at 800 °C for the copolymer with 52 wt% epoxy. The behavior was compared to previously reported benzoxazine/epoxy combinations and was found to be advantageous. The curing behavior of different copolymer compositions was also investigated via DSC and a methodology for matching each peak with its corresponding reaction was developed. Results showed that the alternating favorability of the reactions was dependent on the benzoxazine/epoxy ratio. Overall, the prepared PBZ/epoxy copolymers displayed higher thermal stability than their individual components, indicating suitability for a number of potential extended uses including utility in higher temperature applications.

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

Preparation and electrochemical properties of high-entropy oxide Li x (CrMnCoNiZn) 3-x O 4

High-entropy oxides (HEOs) have gained significant attention as anode materials for lithium-ion batteries (LIBs) due to their high theoretical specific capacity, synergistic effects of constituent elements, and enhanced structural stability induced by high entropy. Here, this study investigates the electrochemical properties of a novel series of HEOs, Li x (CrMnCoNiZn) 3-x O 4 , synthesized via the sol-gel method. As lithium content increases, the electrochemical lithium storage performance of the HEOs improves, attributed to the rise in high-valence states and oxygen vacancies. The high valence state of elements facilitates greater electron transfer, enhancing the specific capacity during lithium insertion. Additionally, a higher concentration of oxygen vacancies boosts ionic conductivity and lithium ion diffusion kinetics, leading to superior electrochemical performance. Among the synthesized materials, Li 0.11 (CrMnCoNiZn) 2.89 O 4 exhibited the best performance, delivering a discharge capacity of 365 mAh·g −1 after 100 cycles at 100 mA·g −1 , 257 mAh·g −1 after 1000 cycles at 1 A·g −1 , and a rate capacity of 196 mAh·g −1 at 2 A·g −1 . The Li + diffusion coefficient reached 2.78 × 10 −15 cm 2 ·s −1 . This work not only deepens the understanding of HEOs' electrochemical behavior in LIBs but also provides insights into the impact of lithium ion substitution on their performance.

25 ENERGY STORAGE↗
DOE OSTI2022

Process and feedstock driven microstructure for laser powder bed fusion of 316L stainless steel

Here in the pursuit of improving additively manufactured (AM) component quality and reliability, fine-tuning critical process parameters such as laser power and scan speed is a great first step toward limiting defect formation and optimizing the microstructure. However, the synergistic effects between these process parameters, layer thickness, and feedstock attributes (e.g. powder size distribution) on part characteristics such as microstructure, density, hardness, and surface roughness are not as well-studied. In this work, we investigate 316L stainless steel density cubes built via laser powder bed fusion (L-PBF), emphasizing the significant microstructural changes that occur due to altering the volumetric energy density (VED) via laser power, scan speed, and layer thickness changes, coupled with different starting powder size distributions. This study demonstrates that there is not one ideal process set and powder size distribution for each machine. Instead, there are several combinations or feedstock/process parameter ‘recipes’ to achieve similar goals. This study also establishes that for equivalent VEDs, changing powder size can significantly alter part density, GND density, and hardness. Through proper parameter and feedstock control, part attributes such as density, grain size, texture, dislocation density, hardness, and surface roughness can be customized, thereby creating multiple high-performance regions in the AM process space.

316L stainless steel↗
DOE OSTI2021

The surface triple-coupling on single crystalline cathode for lithium ion batteries

Single crystalline (SC) cathode materials, which are less susceptible to micro/nano-cracks formation and offer better structure stability compared to the polycrystalline counterpart, have attained great attention. However, the parasitic side reactions at the cathode-electrolyte interface induces the loss of active species, which consequently leads to continual degradation of the electrochemical performances. Herein, a triple coupling of concentration-gradient Na+, F- co-doping and surface NaF coating are exploited for the first time on SC LiNi 0.5C o 0.2 Mn 0.3 O 2 cathode by the hydrolysis of NaPF 6 . This process regulates the external structure of materials by constructing a “sandwich” configuration from surface to bulk: rock salt - mixing zone - layered phase. The detailed interface transformation mechanism is revealed by Neutron powder diffraction (NPD), spherical aberration corrected high-resolution scanning transmission electron microscopy (HR-STEM), electron energy loss spectroscopy (EELS), and Ar+ sputtering assisted X-ray photoelectron spectroscopy (XPS). The synergistic effects endow the SC cathode with outstanding capacity retentions: 91.3% at 25 °C and 85% at 45 °C, after 500 cycles at 5 C between 3.0 and 4.5 V. In addition, a high full-cell reversible capacity of 168.9 mAh g -1 with a capacity retention of 92.4% is achieved after 300 cycles at 1 C. Multiple characterizations further indicate that these superior results are mainly ascribed to the overall structure integrity of SC material, the thin cathode electrolyte interface, high content of lithium fluoride, and the low solubility of transition metal ions. This work opens a new avenue to construct a benign interface towards high-performance lithium ion batteries.

lithium ion batteries↗
DOE OSTI2026

Reducing Non-Radiative Recombination in Perovskite Solar Cells with a SiO2-Graphene Oxide Buried Interface Layer

Perovskite solar cells (PSCs) have emerged as a transformative photovoltaic technology. However, the device performance of inverted PSCs is dramatically limited by surface defects and the underlying film morphology of metal halide perovskite (MHP) thin film. Herein, we report a novel buried interface layer consisting of SiO2 nanoparticles (NPs) chemically bonded to graphene oxide (GO), deposited atop a hydrophobic hole extraction layer (HEL) to address this limitation. The SiO2 NPs serve as insoluble scaffolds that immobilize GO sheets on the hydrophobic HEL surface, enabling the formation of homogeneous MHP thin films. Meanwhile, the GO functional groups interact with surface-uncoordinated Pb2+, suppressing interfacial defects and guiding crystal grain growth of the resultant MHP thin films. This synergistic effect suppresses non-radiative charge recombination and enhances charge extraction efficiency. As a result, a 26.07% efficiency with significantly suppressed photocurrent hysteresis is observed from PSCs incorporating the SiO2-GO buried interface layer. Moreover, the above PSCs maintain 92% of their initial PCE after 1800 h of continuous operation at the maximum power point under AM 1.5 G (100 mW/cm2) illumination at 25 degrees C in air with 50-60% relative humidity. These results demonstrate that we have developed a facile and effective way to realize high-performance inverted PSCs.

14 SOLAR ENERGY↗
DOE OSTI2022

Exploring the potential of high entropy perovskite oxides as catalysts for water oxidation

Electrochemical water splitting is a promising technology to renewably generate hydrogen from water with no carbon footprint. However, the catalytic efficiency is hindered by the sluggishness of the oxygen evolution reaction (OER) at the anode. Therefore, developing earth-abundant, stable, and efficient OER catalysts is of keen interest. Recent studies have demonstrated that high entropy perovskite oxides (HEPOs) can exhibit superior OER activity and excellent electrochemical stability due to the synergistic effects of the multiple cations and the high entropy configuration effect. In this opinion paper, we point out the strengths and discuss the challenges and future prospects for HEPO-based electrocatalysts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

EPS8 supports pancreatic cancer growth by inhibiting BMI1 mediated proteasomal degradation of ALDH7A1

Aldehyde dehydrogenase 7 family member A1 (ALDH7A1) is an enzyme catalyzing lipid peroxidation of fatty aldehydes. It plays a critical role in sustaining high oxygen consumption rate (OCR) and ATP production in pancreatic ductal adenocarcinoma (PADC). However, why PADC cells maintain a relatively high level of ALDH7A1 concentration is still not well understood. In the current study, we explored the interplay between epidermal growth factor receptor kinase substrate 8 (EPS8) and ALDH7A1 in PADC cells. PADC cell lines MIA PaCa-2 and AsPANC-1 were used for in vitro and in vivo studies. The co-IP assay showed mutual interactions between Flag-EPS8 and Myc-ALDH7A1 in both MIA PaCa-2 and AsPANC-1 cells. EPS8 knockdown resulted in decreased ALDH7A1 protein levels and increased poly-ubiquitination. An interaction was observed between ALDH7A1 and BMI1 but not between BMI1 and EPS8. BMI1 knockdown reduced ALDH7A1 poly-ubiquitination and degradation caused by EPS8 knockdown. Dual EPS8 and ALDH7A1 knockdown had a synergistic effect on suppressing PADC cell proliferation in vitro and in vivo. In conclusion, this study revealed that EPS8 supports PADC growth by interacting with ALDH7A1 and inhibiting BMI1 mediated proteasomal degradation of ALDH7A1.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2022

Binary Fe/Mn-Based Nanocomposites as Li-Free Cathode Materials for Li Batteries Assembled in Charged State

Li-ion batteries play important roles in this mobile society. The ever-increasing demand for energy storage, particularly from electric vehicles, requires next-generation Li batteries with higher energy density and better safety. In contrast to existing Li-ion batteries using lithiated cathodes and Li-free anodes, we explore Li-free cathodes coupled with lithium/ lithiated anodes in order to construct new Li batteries assembled in a charged state. Here, two highly promising Li-free cathode materials of 1-D FeOF nanorods and 2-D monolayer MnO 2 nanosheets are integrated to make FeOF@MnO 2 nanocomposites. FeOF nanorods are sandwiched by monolayer MnO 2 nanosheets where FeOF nanoparticles could prevent the restacking of the monolayer MnO 2 nanosheets and the presence of monolayer MnO 2 nanosheets could enhance the electrical integration of the FeOF nanorods. Synergistic effects of the binary Fe/Mn-based cathodes can lead to both high voltage and high capacity, compared to individual components. Electrochemical evaluation reveals that binary Fe/Mn-based Li-free cathodes demonstrate promising performances and are worthy of further investigation and optimization.

25 ENERGY STORAGE↗
DOE OSTI2022

Stabilization of Dinuclear Rhodium and Iridium Clusters on Layered Titanate and Niobate Supports

Atomically dispersed organometallic clusters can provide well-defined nuclearity of active sites for both fundamental studies as well as new regimes of activity and selectivity in chemical transformations. More recently, dinuclear clusters adsorbed onto solid surfaces have shown novel catalytic properties resulting from the synergistic effect of two metal centers to anchor different reactant species. Difficulty in synthesizing, stabilizing, and characterizing isolated atoms and clusters without agglomeration challenges allocating catalytic performance to atomic structure. Here, we explore the stability of dinuclear rhodium and iridium clusters adsorbed onto layered titanate and niobate supports using molecular precursors. Both systems maintain their nuclearity when Statistical analysis of HAADF-STEM images revealed that rhodium and iridium dimers had mean cluster-to-cluster distances very similar to what is expected from a random distribution of atoms over a large area, indicating that they are dispersed without aggregation. The stability of dinuclear rhodium clusters supported on titanate nanosheets was also investigated by X-ray absorption fine structure (EXAFS), DRIFTS, and first-principles calculations. Both X-ray absorption spectroscopy and HAADF-STEM simulations, guided by density functional theory (DFT)-optimized structure models, suggested that rhodium dimers adsorb onto the nanosheets in an end-on binding mode that is stable up to 100 degrees C under reducing conditions. Finally, this study highlights that crystalline nanosheets derived from layered metal oxides can be used as model supports to selectively stabilize dinuclear clusters, which could have implications for heterogeneous catalysis.

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

From Electronic Structure to Ion Transport: Photoelectron Spectroscopy and Molecular Dynamics Simulations Reveal the Role of Anions in Lithium Battery Electrolytes

Electrolyte anions are pivotal for lithium battery performance, yet their fundamental electronic structural properties are not well understood. In this work, we employ a combination of negative-ion photoelectron spectroscopy (NIPES), ab initio calculations, and molecular dynamics (MD) simulations to investigate the electronic structures of three representative electrolyte anions. This multiscale approach enables us to elucidate how their intrinsic electronic properties govern anion–solvent interactions in gas-phase clusters, as well as lithium-ion (Li + ) solvation structures and ion transport behavior in the condensed phase. NIPES reveals that difluoro(oxalato)borate (DFOB – ), bis(fluorosulfonyl)imide (FSI – ), and bis(oxalato)borate (BOB – ) all exhibit high electron binding energies, with vertical/adiabatic detachment energies increasing from DFOB – (6.09/5.70 eV) to FSI – (6.80/6.10 eV) to BOB – (6.82/6.40 eV), correlating with enhanced oxidation stability. Ab initio calculations reveal that DFOB – /FSI – –solvent complexes bind Li + ∼ 10 kcal/mol stronger than BOB – series, aligning with the strength of a Li + –anion model. DFOB – exhibits pronounced charge localization on both oxygen and fluorine atoms, enabling their involvement in Li + coordination. In contrast, fluorine atoms in FSI – are largely electron-depleted and remain excluded from direct Li + binding. MD simulations further demonstrate that LiDFOB and LiFSI systems exhibit Li + diffusion coefficients three and five times higher than those of LiBOB across four common solvents. Notably, LiFSI salt in acetonitrile (AN) exhibits the fastest Li + diffusion among 12 electrolyte systems, highlighting the synergistic effect of FSI – and AN in promoting ion mobility. In conclusion, these findings provide a molecular-level understanding of the critical roles of anion and its microsolvation in optimizing Li + diffusion dynamics, once again emphasizing the positioning of FSI – and DFOB – as prime candidates for next-generation electrolytes.

25 ENERGY STORAGE↗
DOE OSTI2022

Molecular Driving Force for Facet Selectivity of Sequence-Defined Amphiphilic Peptoids at Au–Water Interfaces

Shape-controlled colloidal nanocrystal syntheses often require facet-selective solution-phase chemical additives to regulate surface free energy, atom addition/migration fluxes or particle attachment rates. Because of their highly tunable properties and robustness to a wide range of experimental conditions, peptoids represent a very promising class of next generation functional additives for control over nanocrystal growth. However, understanding the origin of facet selectivity at the molecular level is critical to generalizing their design. In this work, we employ molecular dynamics simulations and biased sampling methods and report stronger selectivity to Au(111) than to Au(100) for Nce3Ncp6, a peptoid that has been shown to assist the formation of five-fold twinned Au nanostars. We find that facet-selectivity is achieved through synergistic effects of both peptoid-surface and solvent-surface interactions. Moreover, the amphiphilic nature of Nce3Ncp6 together with the order of peptoid-peptoid and peptoid-surface binding energies, i.e., peptoid-Au(100) < peptoid-peptoid < peptoid-Au(111), further amplifies its distinct collective behavior on different Au surfaces. Our studies provide a fundamental understanding of the molecular origin of facet-selective adsorption and highlight the possibility of future designs and uses of sequence-defined peptoids for predictive syntheses of nanocrystals with designed shapes and properties.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Nonane and Hexanol Adsorption in the Lamellar Phase of a Nonionic Surfactant: Molecular Simulations and Comparison to Ideal Adsorbed Solution Theory

Adsorption of n-nonane/1-hexanol (C9/C6OH) mixtures into the lamellar phase formed by a 50/50 w/w triethylene glycol mono-n-decyl ether (C10E3)/water system was studied using configurational-bias Monte Carlo simulations in the osmotic Gibbs ensemble. The interactions were described by the Shinoda–Devane–Klein coarse-grained force field. Prior simulations probing single-component adsorption indicated that C9 molecules preferentially load near the center of the bilayer increasing the bilayer thickness, whereas C6OH molecules are more likely to be found near the interface of the polar and non-polar moieties swelling the bilayer in the lateral dimension. Here, we extend this work to binary C9/C6OH adsorption to probe whether the difference in the spatial preferences may lead to a synergistic effect and enhanced loadings for the mixture. Comparing loading trends and the thermodynamics of binary adsorption to unary adsorption reveals that C9–C9 interactions lead to the largest enhancement, whereas C9–C6OH and C6OH–C6OH interactions are less favorable for this bilayer system. As a result, ideal adsorbed solution theory yields satisfactory predictions of the binary loading.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Unraveling In-Situ Formation of Surface Nickel Nitride Structures in Plasma-Assisted Catalytic Ammonia Synthesis

We report the in situ formation of Ni nitride for plasma-assisted ammonia synthesis. Both the surface nitrogen concentration and the ammonia formation rate exhibit dependence on the N 2 :H 2 feed ratio. The maximum surface nitrogen concentration occurs at a N 2 :H 2 ratio of 4:1, and the maximum catalytic activity occurs at 2:1. In contrast, the formation of gas phase radicals is less sensitive to feed composition, indicating that Ni nitride is more kinetically relevant to ammonia production than gas-phase radicals. The plasma-induced formation of Ni nitride is therefore proposed to be a critical contributor to the synergistic effects in plasma-assisted catalytic ammonia synthesis. Additionally, Ni nitride alters the surface reaction mechanism of plasma-assisted ammonia synthesis, with the rate-determining-step (RDS) shifting to surface-bound NH 3 formation rather than N 2 activation at temperatures below 373 K. These findings provide mechanistic insight that opens opportunities for optimizing the performance of plasma-assisted catalytic ammonia synthesis

Ammonia↗