Molten Salt Flux Research Articles

Preparation of Single-Crystal Li-Rich Mn-Based Layered Oxides with Excellent Electrochemical Performance via Simple Stepwise High-Temperature Sintering.

Li-rich Mn-based layered oxides have attracted extensive attention in lithium-ion battery cathode materials due to their high specific capacity, wide operating voltage, and low cost. However, the large-scale production of single-crystal Li-rich Mn-based layered oxides remains a significant challenge. Herein, the morphology, structure, and electrochemical properties of a series of samples (Li1.2Ni0.13Co0.13Mn0.54O2) prepared by the solid-state method and the molten-salt flux method were assessed. Single-crystal particles exactly could be prepared by potassium chloride (KCl), but its electrochemical performance was inferior and the molten-salt flux method was too complicated for industry. Surprisingly, we found that water washing and annealing processes could enhance the cycling performance. Furthermore, single-crystal Li1.2Ni0.13Co0.13Mn0.54O2 with a particle size of 536 nm was successfully prepared by simple stepwise sintering (950 °C for 7 h, 1000 °C for 1 h, and 850 °C for 2 h), which delivered a specific capacity of 274.9 mAh·g-1 between 2.0 and 4.8 V at 0.1 C with 77.4% initial Coulombic efficiency and 82.1% capacity retention after 100 cycles at 0.1 C. This study may provide theoretical guidance for the industrial production of single-crystal Li-rich Mn-based layered oxides.

Molten flux growth of single crystals of quasi-1D hexagonal chalcogenide BaTiS3

BaTiS3, a quasi-1D complex chalcogenide, has gathered considerable scientific and technological interest due to its giant optical anisotropy and electronic phase transitions. However, the synthesis of high-quality BaTiS3 crystals, particularly those featuring crystal sizes of millimeters or larger, remains a challenge. Here, we investigate the growth of BaTiS3 crystals utilizing a molten salt flux of either potassium iodide, or a mixture of barium chloride and barium iodide. The crystals obtained through this method exhibit a substantial increase in volume compared to those synthesized via the chemical vapor transport method, while preserving their intrinsic optical and electronic properties. Our flux growth method provides a promising route toward the production of high-quality, large-scale single crystals of BaTiS3, which will greatly facilitate advanced characterizations of BaTiS3 and its practical applications that require large crystal dimensions. Additionally, our approach offers an alternative synthetic route for other emerging complex chalcogenides.Graphical

Alkali rare earth double phosphates: Promising new high temperature scintillators

Alkali rare earth double phosphates were investigated for their X-ray induced scintillation. Double phosphates with stoichiometry A3Ln(PO4)2 (A = K or Rb, Ln = Eu or Tb) were synthesized via a eutectic molten salt flux yielding high quality single crystals. The systematic variation of the alkali and rare earth elements in the structure allowed for insights into the effects of the chemical composition on the scintillation output. The radioluminescence of these compositions under X-ray excitation is reported with a discussion of the variance of their luminosity as a function of both the constituent alkali and lanthanide elements. The relative luminosity of Rb3Tb(PO4)2 surpasses BGO by 30 %. The dependance of the scintillation on temperature is also investigated, including an unusual peak intensity increase for higher temperatures that can reach 1.4x of its value at room temperature for Rb3Tb(PO4)2 at 255 °C, and 2.1x for K3Tb(PO4)2 at 495 °C.

Exploring the Valence Diversity of Uranium by Flux Growth of Uranium Silicate under Inert Atmosphere.

The attributes of good solubility and the redox-neutral nature of molten salt fluxes enable them to be useful for the synthesis of novel crystalline actinide compounds. In this work, a flux growth method under an inert atmosphere is proposed to explore the valence diversity of uranium, and a series of five uranium silicate structures, [K3Cl][(UVIO2)(Si4O10)] (1), Cs3[(UVO2)(Si4O10)] (2), K2[UIV(Si2O7)] (3), K8[(UVIO2)(UVO2)2(Si8O22)] (4), and Cs6[UIV(UVO)2(Si12O32)] (5), were synthesized using different metal halide salt and feeding U/Si ratios. Crystal structure analysis reveals that the utilization of argon atmosphere that helps to avoid possible oxidation of low-valence uranium generates a variety of oxidation states of uranium including U(VI), U(V), U(IV), mixed-valence U(V) and U(VI), and mixed-valence U(IV) and U(V). Characterization of physicochemical properties of representative compounds shows that all these uranium silicate compounds have bandgaps among the range of 2.0-3.4 eV, and mixed-valence uranium silicate compounds have relatively narrower bandgaps. Density functional theory calculations on formation enthalpies, lattice energies, and bandgaps of all five compounds were also performed to provide more structural information about these uranium silicates. This work enriches the library of variable-valence uranium silicate compounds and provides a feasible way to produce novel actinide compounds with intriguing properties through the flux growth method that might show potential application in relevant fields such as storage media for nuclear waste.

Phase formation, microstructural and dielectric properties of bismuth ferrite nanoceramics synthesized by low-temperature molten salt flux route

BiFeO3 nano-ceramics were synthesized using the low-temperature molten salt synthesis route to study the influence of calcination temperature and salt ratios. The Rietveld refinement revealed the distorted perovskite structure of BFO. These granular-shaped BFO samples’ grains morphology was studied using the FESEM. The FTIR revealed the presence of Metal-Oxygen bonds in the BFO ceramics. The XPS studies exhibited the respective constituent elements’ oxidation states and validated the presence of oxygen ion vacancies. The frequency-dependent dielectric properties were measured at various temperatures. The electrical conductivity measurement showed a linear variation as a function of frequency which validated Jonscher’s power law.

Cooking in Salt for Ultra-Clean Superconductor UTe2

A new crystal growth technique, the molten salt flux liquid transport method, was developed to produce high-quality single crystals of spin-triplet superconductor UTe2. This method is promising for exploring the exotic superconductivity of other materials.

Sub-50 nm perovskite-type tantalum-based oxynitride single crystals with enhanced photoactivity for water splitting

A long-standing trade-off exists between improving crystallinity and minimizing particle size in the synthesis of perovskite-type transition-metal oxynitride photocatalysts via the thermal nitridation of commonly used metal oxide and carbonate precursors. Here, we overcome this limitation to fabricate ATaO2N (A = Sr, Ca, Ba) single nanocrystals with particle sizes of several tens of nanometers, excellent crystallinity and tunable long-wavelength response via thermal nitridation of mixtures of tantalum disulfide, metal hydroxides (A(OH)2), and molten-salt fluxes (e.g., SrCl2) as precursors. The SrTaO2N nanocrystals modified with a tailored Ir–Pt alloy@Cr2O3 cocatalyst evolved H2 around two orders of magnitude more efficiently than the previously reported SrTaO2N photocatalysts, with a record solar-to-hydrogen energy conversion efficiency of 0.15% for SrTaO2N in Z-scheme water splitting. Our findings enable the synthesis of perovskite-type transition-metal oxynitride nanocrystals by thermal nitridation and pave the way for manufacturing advanced long-wavelength-responsive particulate photocatalysts for efficient solar energy conversion.

The formation mechanism of NaLiTi3O7 and its effect on Li4Ti5O12 prepared by the NaCl molten salt flux method

Octahedral single-crystal Li4Ti5O12 materials with {111} crystalline surfaces exposed are prepared in NaCl flux, but the presence of NaLiTi3O7 in the product deteriorates the electrochemical performance of Li4Ti5O12 materials. Herein, the formation mechanism of NaLiTi3O7 in the product was discussed, and it was suggested that the impurity content is affected by the diffusion of the raw materials in the NaCl molten salt flux. The more NaCl is present, the more NaLiTi3O7 is generated. Because Li2O and TiO2 are separated by the salt, and both reactants should diffuse a much longer distance to react. Once the ratio of Li2O and TiO2 reaches 1:3, NaLiTi3O7 will form immediately; otherwise, if the ratio reaches 2:5, Li4Ti5O12 forms. Based on this hypothesis, NaLiTi3O7 will form because there is not enough Li2O to react with TiO2 to form Li4Ti5O12. Therefore, the content of Li2CO3 in the material preparation process was increased, allowing more Li2O to come into contact with TiO2 in the NaCl flux, thereby increasing the probability of Li4Ti5O12 formation and reducing the generation of NaLiTi3O7. Two modification strategies have been proposed to inhibit the generation of impurities. It was found that increasing the amount of Li2CO3 to 15 wt % in excess can reduce impurities of NaLiTi3O7, and further increasing its amount will cause the occurrence of new impurities. Adding a small amount of LiCl to the precursor mixtures can also inhibit NaLiTi3O7 generation in the prepared LTO materials and improve their electrochemical performances.

BaCu2SiS4: A New Member of the AIIBI2MIVQ4 Chalcogenide Family with a Chiral Crystal Structure

AbstractNoncentrosymmetric ternary and quaternary chalcogenides are studied as promising nonlinear optical (NLO) materials in the mid‐infrared region. Here, we report the synthesis of a new material BaCu2SiS4 in the AIIBI2MIVQ4 family (A=divalent metal; B=monovalent metal; M=tetrel, Q=chalcogen), and discuss its crystal structure, thermal stability, optical behavior, and electronic structure. BaCu2SiS4 crystallizes in the noncentrosymmetric chiral space group P3221 with lattice parameters a=6.1440(3) Å, c=15.3542(8) Å, V=501.95(6) Å3, Z=3. The structure features helical channels formed by corner‐sharing [CuS4] and [SiS4] tetrahedral units. Synthesis was carried out in a molten salt flux, as opposed to a traditional solid‐state route from elements, to minimize the formation of a competing ternary phase, Ba2SiS4. BaCu2SiS4 is a semiconductor with an experimentally‐determined direct bandgap of ~2.2 eV. The material exhibits second harmonic generation (SHG) activity, confirming the noncentrosymmetric nature of the structure. Analysis of reported AIIBI2MIVQ4 crystal structures pointed out a correlation among potential structure types and the radii of the constituent elements. Total energy calculations were carried out to explore the relative stability of several reported crystal structures in this family of compounds.

Evaluation of magnetic anisotropy in oriented plate-shaped strontium ferrite particles

Plate-shaped hexagonal SrFe12O19 particles, synthesized using potassium bromide as the molten salt flux, were dispersed in the resin using a planetary ball mill. Oriented sheets were prepared by coating the dispersion onto the films under a magnetic field. The coercive force and squareness ratio of the oriented sheets were 412 kA m−1 and 0.91, respectively. The magnetic anisotropy field was determined by measuring the rotational hysteresis losses of the oriented sheets with a magnetic torque meter. The anisotropy field was distributed in the range of approximately 200–1100 kA m−1, and particles with an anisotropy field of 478 kA m−1 comprised the majority. The magnetic anisotropy energy estimated from the magnetic anisotropy field was 104 KJ m−3. Assuming a reduction in the crystalline anisotropy field along the c-axis due to simply the shape anisotropy field resulting from the platelet shape of the particles, particles occupying the majority exhibited a maximum anisotropy field of 823 kA m−1.

Characterization of plate-shaped strontium ferrite particles synthesized via co-precipitate and heat treatment in molten potassium bromide flux

Plate-shaped hexagonal strontium ferrite particles were synthesized using potassium bromide as the molten salt flux. The co-precipitate of strontium and iron hydroxides was heated in the temperature range of 670–870 °C in the flux. Clear peaks based on hexagonal ferrite and weak peaks based on α-Fe2O3 were observed after the heat treatment at 670 °C. The peaks based on α-Fe2O3 almost disappeared after the heat treatment at 730 °C, and the peaks observed in the particles heated at temperatures higher than 730 °C were consistent with the standard data for SrFe12O19. The particle shape tended to change from a hexagonal plate shape to a rounded plate shape with increasing temperature while maintaining a particle diameter of approximately 100–200 nm. The coercive force was approximately 420–440 kA/m, while the magnetization at the applied field of 1353 kA/m was approximately 62 Am2/kg at heating temperatures higher than 750 °C.

Highly textured zinc aluminate: Nd, Ce films over sapphire for NIR emitting applications

The development of sapphire-compatible optical sources is highly valued due to the potential cost-effective applications in sapphire-based integrated devices. In this work, a screen printing technique assisted by a molten salt flux was used to synthesize (hk0)-textured ZnAl2O4: Nd, Ce sub-micron films deposited over the sapphire substrate. The study is focused at controlling Ce concentration in the emitting layers, as well as determining the key parameters to be met for the development of ZnAl2O4-based films of high efficiency and remarkable optical properties. A degree of crystallinity of the ZnAl2O4-based films, and a precise adjustment of texture are the keys parameters for further improvement of NIR luminescence efficiency. Specifically, (hk0)-textured films were developed at sintering temperature of around 1300 °C, which contributed to a higher NIR emission intensity as compared to that of (hkl)-untextured films. Therefore, the design process carried out in this work promotes a feasible way to achieve a high NIR emission performance, demonstrating the validity of the approach for a wide range of applications.

Molten salt flux synthesis of cobalt doped refractory double perovskite Sr 2CoxGa1-xNbO6: A spectroscopic investigation for multifunctional materials

A simple and cost-effective salt synthesis route toward refractory oxides of composition Sr 2Ga1-xCoxNbO6 has been carried out. Herein, we report on the refinement of the set of parameters related to heat treatment to stabilize the ordered perovskite for cobalt content, x, ranging from 0.02 to 0.2. The parameters studied were the nature of the flux, the dwell temperature, the dwell time and the cooling rate for a given cobalt precursor. Our study relied on powder X-ray diffraction, UV–visible-near IR (UV–vis–NIR), Electron Spin Resonance (ESR) and Nuclear Magnetic Resonance (NMR) experiments allowing us to better understand the room temperature electronic structure. The tuning of energy gap with the cobalt content, mixed spin state Co3+ (Low Spin ​+ ​Intermediate/High Spin) at room temperature and the brown shades of these materials render them the multifunctionality.

Single crystal growth of superconducting UTe2 by molten salt flux method

The molten salt flux method is applied as a synthetic route for the single crystals of the spin-triplet superconductor ${\mathrm{UTe}}_{2}$. The single crystals under an optimized growth condition with excess uranium exhibit a superconducting transition at ${T}_{\mathrm{c}}=2.1\phantom{\rule{4pt}{0ex}}\mathrm{K}$, which is the highest ${T}_{\mathrm{c}}$ reported for this compound. The obtained crystals show a remarkably large residual resistivity ratio with respect to the room temperature value and a small residual electronic contribution in specific heat well below ${T}_{\mathrm{c}}$. These results indicate that the increase of ${T}_{\mathrm{c}}$ in ${\mathrm{UTe}}_{2}$ can be achieved by reducing the disorder associated with uranium vacancies. The excess uranium in the molten salt acts as a reducing agent, preventing tetravalent uranium from becoming pentavalent and suppressing creation of uranium vacancies. At the same time, the relatively low growth temperature can suppress Te volatilization.

Two tetravalent uranium silicate and germanate crystals with three membered single-ring by molten salt method: K2USi3O9 and Cs2UGe3O9

Two tetravalent uranium silicate and germanate M2UIVT3O9 (M = K, Cs; T = Si, Ge) crystals were crystalized under inert gas by molten salt flux growth method. K2USi3O9 (1) crystallizes in the monoclinic space group P121/n1 with lattice parameters a = 7.1076 Å, b = 10.4776 Å, c = 12.2957 Å, γ = 120° and V = 915.67 Å3. Cs2UGe3O9 (2) crystallizes in a hexagonal space group P-6 with lattice constants of a = 7.5138 Å, b = 7.5138 Å, c = 11.0114 Å, γ = 120° and V = 538.38 Å3. Bond valence calculations indicate tetravalent uranium in both structures, which contain three-membered single-ring T3O96− trimers. K2USi3O9 is the first uranium silicate that contains the Si3O96− trimers.

Molten Salt Flux Synthesis, Structure determination, Optical, Impedance and Modulus Spectroscopy Characterization of perovskite compound

The chemical Molten Salt Flux process was used for the synthesis of Ba0.97La0.02Ti1-xNb4x/5O3 polycrystalline sample (well-known as BLTi0.93Nb0.056). Doping with Niobium caused significant alterations in the physical properties of BLT ceramic. The XRD analysis revealed that Nb introduction forms a pure perovskite phase and crystallize in the P4/mmm-tetragonal symmetry. The average crystallite size was proven to decrease with the increase in Nb concentration. TEM image showed the formation of particles, where the average grain size decreased with Nb doping. The Nb incorporation into the BLT host lattice was also confirmed by the optical band gap (Eg) value. The optical properties were strongly influenced by Nb doping. The dielectric parameters were subsequently investigated as a function of frequency and d.c bias voltage. The observed dielectric dispersion was interpreted on the basis of Maxwell-Wagner interfacial model and Koop's phenomenological theory. Overall, Nyquist plot shows both bulk and grain boundary effect. The electrical relaxation process occurring in the material has been found to be d.c bias voltage dependent. Modulus analysis has established the possibility of hopping mechanism for electrical transport processes in the system.

(Invited) Electrochemical Recycling of Used Nuclear Fuel

Current nuclear energy systems produce approximately twenty percent of the electricity generated in the U.S. and account for approximately fifty-five percent of the carbon-free electricity. As the U.S. strives for even lower carbon emissions such as net-zero carbon emission by 2050, nuclear energy will play an increased role in providing baseload electricity to the nation. An opportunity to implement advanced reactor and fuel cycle technologies that offer enhanced resource utilization, waste management and non-proliferation features will be available as the role of nuclear energy expands to meet the growing demand of carbon-free electricity. For example, the U.S. can transition from the current once-through fuel cycle to a closed fuel cycle with used fuel recycling that provides actinides for energy production and encapsulates fission product waste in durable, engineered waste forms.Argonne National Laboratory has a rich-history in developing new methods to recycle used nuclear fuels that dates back to the late 1950s. This early work focused on developing methods to recycle the actinides extracted from used nuclear fuel and closing the nuclear fuel cycle. Early techniques consisted of melting the used metallic fuel discharged from the Experimental Breeder Reactor II in lime-stabilized zirconia crucibles to produce a liquid uranium alloy that could be separated from the resulting oxide dross containing the fission product elements. The resulting uranium alloy was recycled to produce fresh nuclear fuel. Subsequently, more elegant techniques such as molten salt – liquid metal extraction processes were developed to recover and recycle the actinides present in the oxide dross, and to separate the actinides from the fission product elements present in used metallic fuel. In both cases, the actinides were recycled in fresh nuclear fuel and the fission products were sequestered in waste forms.Argonne’s research and development efforts in used fuel recycling expanded to include areas such as oxide to metal conversion via chemical reduction in a molten salt flux and developing new processes for recycling the actinides extracted from nitride and carbide fuels. Work in this area evolved to include the design and development of electrochemical technologies for recovering actinide metals from used nuclear fuels and an electrolytic reduction process for the conversion of metal oxides to metallic forms.The transition of used nuclear fuel processing from chemical to electrochemical methods established the need for fundamental electrochemical data for the actinide and fission product elements in molten salt media, provided opportunities for the design and demonstration of purpose-built electrochemical processing equipment, and allowed for the use of process monitoring and control technologies to enable efficient electrochemical cell operations. Actinide metal nucleation and growth in a molten LiCl - KCl eutectic salt is an example of the type of fundamental data that has been collected to elucidate the behavior of actinides during the electrodeposition process. Results from those experiments revealed that actinide nucleation transitions from progressive to instantaneous growth with increasing actinide chloride concentration in the molten salt. This behavior influenced the design of electrochemical processing equipment. Other data such as actinide ion diffusion coefficients were also determined from the experiments.Electroanalytical process monitoring and control techniques are being developed for several molten salt applications. These techniques are ideally suited for molten salt applications due to the specificity of chemistry information that is produced, simplicity of equipment design, and functionality at elevated temperature and in radiation environments. Argonne developed a multi-function sensor and methodology that yields reproducible electrochemical data such as the redox potential of the salt and the identities of species present in the system for applications in used fuel processing and monitoring heat transfer fluids.Argonne’s molten salt activities span the range from fundamental property measurement to pilot-scale process demonstrations. The presentation will provide a survey of Argonne’s electrochemical fuel recycling activities including actinide electrochemistry, process design and development, and electroanalytical sensor development.ACKNOWLEDGMENTS: The submitted abstract has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. The U.S. Government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government.

Synthesis, crystal structure and Na+ transport in Na3La(AsO4)2

Much of the research effort in the past decade has been closely focused on finding suitable solid electrolytes with high ionic conductivity for various applications. In this context, the compound Na3La(AsO4)2 was synthesized using the molten salt (flux) method and its structure was solved from the single-crystal X-ray diffraction data for the first time. Na3La(AsO4)2 crystallizes in the monoclinic space group P21/c (#14) with a ​= ​19.451(4)Å; b ​= ​5.554(1)Å; c ​= ​14.365(3)Å; β ​= ​90.035(2)°. Its crystal structure consists of an open 3D network built of [LaO8] polyhedra sharing oxygen corners and edges with neighboring [AsO4] tetrahedra. Tunnels in the [010] direction accommodate Na+ cations. The ionic conductivity was investigated experimentally and computationally. High-temperature ac-conductivity measurements yielded the highest ionic conductivity of 1.93 ​× ​10−4 ​S ​cm−1 ​at 700 ​°C with the apparent activation energy Ea ​= ​0.85eV. A complementary analysis through the bond valence site energy calculation (BVSE), revealed that the structure of Na3La(AsO4)2 favors a 3D ionic diffusion pathway with the empirical activation energy of 1.061 ​eV for the long-range migration of Na+ ions.

Aluminate-Based Nanostructured Luminescent Materials: Design of Processing and Functional Properties.

Interest in luminescent materials has been continuously growing for several decades, looking for the development of new systems with optimized optical properties. Nowadays, research has been focused on the development of materials that satisfy specific market requirements in optoelectronics, radioelectronics, aerospace, bio-sensing, pigment applications, etc. Despite the fact that several efforts have made in the synthesis of organic luminescent materials, their poor stability under light exposure limits their use. Hence, luminescent materials based on inorganic phosphors are considered a mature topic. Within this subject, glass, glass-ceramics and ceramics have had great technological relevance, depending on the final applications. Supposing that luminescent materials are able to withstand high temperatures, have a high strength and, simultaneously, possess high stability, ceramics may be considered promising candidates to demonstrate required performance. In an ongoing effort to find a suitable synthesis method for their processing, some routes to develop nanostructured luminescent materials are addressed in this review paper. Several ceramic families that show luminescence have been intensively studied in the last few decades. Here, we demonstrate the synthesis of particles based on aluminate using the methods of sol-gel or molten salts and the production of thin films using screen printing assisted by a molten salt flux. The goal of this review is to identify potential methods to tailor the micro-nanostructure and to tune both the emission and excitation properties, focusing on emerging strategies that can be easily transferred to an industrial scale. Major challenges, opportunities, and directions of future research are specified.

(Student Battery Slam Best Presentation Award Winner) Investigation of Tunable Properties in Single-Crystal LiNi0.5Mn1.5O4 Cathode Materials

The commercialization of lithium-ion batteries has played a pivotal role in the development of consumer electronics and electric vehicles. In recent years, much research has focused on the development and modification of the active materials of electrodes to obtain higher energies for a broader range of applications. High-voltage spinel materials including LiNi0.5Mn1.5O4 -δ (LNMO) have been considered as promising cathode materials to address the increasing demands for improved battery performance due to their high operating potential, high energy density, and stable cycling lifetimes.Spinel LNMO can adopt two crystallographic structures depending on the synthesis conditions: an ordered P4332 structure which contains Ni and Mn on separate octahedral sites and a disordered Fdm structure which contains Ni and Mn in a random arrangement on octahedral sites. The disordered spinel phase requires higher synthesis temperatures than the ordered phase to form and is often associated with the loss of oxygen from the material lattice, as well as the reduction of a small amount of electrochemically inactive Mn4+ to active Mn3+ for overall charge compensation. The differences in structure and Mn oxidation state of LNMO cathode materials can influence the electrochemical performance. Increased structural disorder can increase Li+ transport properties through reducing two-phase transformation domains, leading to improved rate performances. Through manipulation of synthetic parameters, the structural and electronic properties of LNMO can be well controlled during formation. The molten salt synthesis method has become one of the most prominent techniques to synthesize single-crystal layered and spinel materials.In this work, the molten salt synthesis method is used as a technique to tune both the morphology and Mn3+ content of high-voltage LNMO cathodes. The resulting materials are thoroughly characterized by a suite of analytical techniques, including synchrotron X-ray core-level spectroscopy, which are sensitive to the materials properties at multiple length scales. The multidimensional characterization allows us to build a materials library according to the molten salt phase diagram as well as to establish the relationship between synthesis, materials properties, and battery performance. Results of this work show that Mn3+ content is primarily dependent on the synthesis temperature and increases as temperature is increased. Particle morphology is mostly dependent on the composition of the molten salt flux, which can be tailored to obtain well-defined octahedrons enclosed by (111) facets, plates with predominant (11) facets, irregularly shaped particles, or mixtures of these. The electrochemical measurements indicate that the Mn3+ content has a larger contribution to the battery performance of LNMO than morphological characteristics and that a significant amount of Mn3+ could become detrimental to the battery performance. However, with similar Mn3+ contents, morphology still plays a role in influencing the battery cycle life and rate performance.We also employ high spatial resolution, synchrotron X-ray nanodiffraction techniques to identify the presence and quantify the percentage of the ordered versus disordered spinel phases at the individual particle level as LNMO single-crystal particles likely contain local regions of both ordered and disordered regimes which standard lab X-ray diffractometers may be unable to distinguish. The relationship between structural ordering and Mn3+ content is critical to the understanding of the intrinsic chemomechanical and electrochemical properties of LNMO. The insights of molten salt synthesis parameters on the formation and performance of LNMO, with deconvolution of the roles of Mn3+, crystal structure, and morphology, are crucial for continuing studies in the rational design of LNMO cathode materials for high energy Li batteries.