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Inorganic fillers play an important role in improving the ionic conductivity of solid composite electrolytes (SCEs) for Li-ion batteries. Among inorganic fillers, perovskite-type lithium lanthanum titanate (LLTO) stands out for its high bulk Li+ conductivity on the order of 10-3 S cm-1 at room temperature. According to a literature survey, the optimal LLTO filler should possess the following characteristics: i) a single-crystal structure to minimize grain boundaries; ii) a small particle size to increase the filler/polymer interface area; iii) a 1D morphology for efficient interface channels; and iv) cubic symmetry to facilitate rapid bulk Li+ diffusion within the filler. However, the synthesis of single crystal, 1D LLTO nanomaterials with cubic symmetry is challenging. Herein, a flux strategy is developed to synthesize La0.5M0.5TiO3 (LMTO, M═Li, Na, and K) single-crystal nanorods with an A-site-disordered, cubic perovskite phase. The flux media promotes the oriented growth of nanorods, prevents nanorods from sintering, and provides multiple alkali metal ion doping at M sites to stabilize the cubic phase. SCEs compositing the Li+-conducting LMTO nanorods as fillers and poly[vinylene carbonate-co-lithium sulfonyl(trifluoromethane sulfonyl)imide methacrylate] matrix exhibit more than twice the conductivity of the neat polymer electrolyte (30.6 vs 14.0 µS cm-1 at 303 K).

The dealloying corrosion behavior of the FCC Ni20Cr (wt%) in molten LiF-NaF-KF (FLiNaK) salts at 600 °C under varying applied potentials was investigated. Using in-operando electrochemical techniques and a multi-modal suite of characterization methods, we connect electrochemical potential, thermodynamic stability, and electro-dissolution kinetics to the corrosion morphologies. Notably, under certain potential regimes, a micron-scale bicontinuous structure, characterized by a network of interconnected pores and ligaments riched with the composition of the more noble (MN) element, becomes prominent. At other potentials both MN and less noble (LN) elements dealloy but at different rates. The dealloying process consists of lattice and grain boundary diffusion of Cr to the metal/salt interface, interphase Cr oxidation, accompanied by surface diffusion of Ni to form interconnected ligaments. At higher potentials, the bicontinuous porous structure undergoes further surface coarsening. Concurrently, Cr(II), Cr(III), and Ni(II) begin to dissolve, with the dissolution of Ni occurring at a significantly slower rate. When solid-state transport of Cr is exceeded by the interfacial rates, dealloying depths are limited.

Molten salts is a promising medium for heat storage and heat transfer due to their advantages of low cost, low steam pressure, high energy storage density and wide temperature range. In this paper, a new phase change mixture of molten salts with KNO3, NaNO3, ZnCl2, NaF, Na2CO3, NaCl, and MgO as materials has been prepared through a plenty of experiments. The experimental results show that the melting point of some molten salts can be reduced to 202.9°C, and the decomposition temperature can reach 701.3°C. In addition, its thermophysical properties, including specific heat, viscosity and thermal stability, were measured and analyzed. The average specific heat of some molten salts is as high as 2.53 J/(g K), and the average thermal conductivity is as high as 0.77 W/(m K). In the 4-day short-term thermal stability test, the fluctuation of each parameter is minimal, and the overall thermal physical property is relatively stable. Compared with the traditional phase change molten salt, the new hybrid molten salt has a significantly lower melting point, a further improvement in the decomposition temperature, specific heat and other comprehensive thermophysical properties, and a better overall economy, which has important application value in heat transfer and energy storage. [ABSTRACT FROM AUTHOR]

Ionic melts, in the form of ionic liquids and molten salts, are important in many technological aspects such as metal production and energy applications. Cryolite melts constitute an important family especially for the industrial production of Al. The present computational study aims to analyse the effect of different cations on the structure and properties of Al (III) fluorocomplexes in cryolite melts. Cation effects are discussed as the ion pair interactions due to alkali metal cations of cryolite compounds M3AlF6 with M= Li, Na, K, Rb, or Cs for various microclusters using ionic interaction model (IM) and DFT calculations. DFT results for different ion complexes are compared with the energy calculations using a pseudoclassical model for isolated clusters. QTAIM and ELF analyses were performed to understand the nature of interactions in detail. A link between open-shell interactions and decreased ionic conductivity is proposed within the series of K, Rb, and Cs. Environmental effects, such as temperature and presence of other ions, are investigated in detail by DFT analysis. [ABSTRACT FROM AUTHOR]

CO2, a predominant anthropogenic greenhouse gas, emerges as a primary factor in climate change due to the increasing utilization of fossil fuels, necessitating immediate efforts for the development and implementation of strategies like carbon capture and storage (CCS) to mitigate emissions, considering the ongoing dependence on unsustainable energy and transportation resources. The research endeavours to meet the critical requirement for effective CO2 capture through the exploration of novel sorbent materials, with a specific focus on molecularly precise nanoclusters (NCs), aiming to enhance understanding of the catalytic mechanisms in CO2 reduction and design stable, high‐performance sorbents with controllable properties. Advancing the field, the study delves into the synthesis and examination of molecularly precise nanoclusters (NCs), an emerging domain in nanoscience, with a particular emphasis on well‐defined nanoclusters like thiolate‐protected Au, Ag, and Cu NCs. This strategy provides a distinctive foundation for attaining atomic‐level understanding of electrocatalytic CO2 reduction mechanisms, offering a more precise and customized synthesis to overcome challenges associated with polydispersity in conventional nanoparticles. The study highlights the exceptional catalytic activity of specific Au NCs like Au25 in converting CO2 to CO. It surpasses thermodynamic limits. The study also investigates the influence of surface properties, electrostatic, and steric stability on preventing nanocluster aggregation. It emphasizes the potential of molecularly precise nanoclusters as catalysts for CO2 reduction. Additionally, it suggests avenues for advanced sorbent development with improved performance and stability. [ABSTRACT FROM AUTHOR]

Chemical activation in molten salts is a recent development in the field of tailoring activated carbon, where a combination of activating agents is used rather than a single compound. However, a comprehensive understanding of differences in catalytic activity is lacking. So, the question remains which chemical activation method is more beneficial. This research compares the catalytic effect of ZnCl2 as a single activating agent and its eutectic mixture of ZnCl2-KCl-NaCl (60:20:20 mol %). Pinewood shavings were chemically activated at 400 °C in a mass ratio of 5 to 1 (salt to biomass) and then washed to remove the activating agent. Obtained materials were subsequently physically activated using CO2 at 800 °C in an attempt to further increase their surface area. Properties of obtained carbons were characterized by elemental and proximate analyses, ICP-AES, FTIR, gas adsorption (N2, CO2), and adsorption (iodine, methylene blue, and molasses). Chemical activation with ZnCl2 and the eutectic mixture resulted in a surface area of respectively 910 m2/g and 917 m2/g with significant differences in porosity. The eutectic mixture created a greater proportion of micropores. ZnCl2 was more beneficial for mesoporosity which was formed over a broad range, whereas the eutectic mixture created mesopores in a narrower size range (19–27 nm). Subsequent CO2 gasification widened the pores and lowered the surface area, decreasing the adsorption capacity. This study illustrates that employing mixtures of molten salts has several advantages over a single activating agent and might lead to further development of tailor-made activated carbons. [ABSTRACT FROM AUTHOR]

Reducing CO2 emissions is one of the major challenges facing the modern world. The overall goal is to limit global warming and prevent catastrophic climate change. One of the many methods for reducing carbon dioxide emissions involves capturing, utilizing, and storing it at the source. The Carbon Capture in Molten Salts (CCMS) technique is considered potentially attractive and promising, although it has so far only been tested at the laboratory scale. This study evaluates the wear of the main structural components of a prototype for CO2 capture in molten salts—a device designed and tested in the laboratories of AGH University of Kraków. The evaluation focused on a gas barbotage lance and a reactor chamber (made from Nickel 200 Alloy), which were in continuous, long-term (800 h) contact with molten salts CaCl2-CaF2-CaO-CaCO3 at temperatures of 700–940 °C in an atmosphere of N2-CO2. The research used light microscopy, SEM, X-ray, computed tomography (CT), and 3D scanning. The results indicate the greatest wear on the part of the lance submerged in the molten salts (3.9 mm/year). The most likely wear mechanism involves grain growth and intergranular corrosion. Nickel reactions with the aggressive salt environment and its components cannot be ruled out. Additionally, the applied research methods enabled the identification of material discontinuities in the reactor chamber (mainly in welded areas), pitting on its surface, and uneven wear in different zones. [ABSTRACT FROM AUTHOR]

Titanium nitride is an exciting plasmonic material, with optical properties similar to gold. However, synthesizing TiN nanocrystals is highly challenging and typically requires solid‐state reactions at very high temperatures (800–1000°C). Here, the synthesis of TiN nanocrystals is achieved at temperatures as low as 350°C, in just 1 h. The strategy comprises molten salt, Mg as reductant and Ca3N2 as nitride source. This brings TiN from the realm of solid‐state chemistry into the field of solution‐based synthesis in regular, borosilicate glassware. [ABSTRACT FROM AUTHOR]

This research focuses on the description and modeling of a one-dimensional molten salt reactor (MSR), in the presence of thermal feedback. Following the example of previous works, a simple one-dimensional system is proposed, describing a molten salt reactor with a main neutron-multiplying zone called core and a recirculation loop where the salt cools down. Specific attention is paid to the precursors’ drift by modifying the neutron balance equation. Liquid nuclear fuels are characterized by a high volumetric expansion coefficient in comparison to customary solid fuels. Therefore, a strong coupling between neutronics and thermal-hydraulics is expected. As a consequence, a highly negative density coefficient characterizes the thermal feedback on the neutron reactivity. The precursor equation is here inverted analytically and combined with the neutron balance equation to obtain a generalized eigenvalue problem with the neutron flux distribution as the unknown. The balance equations are derived by finite volume integration over a discretized mesh, and the coupling between the two physical models is treated by Picard iterations. The numerical solution is finally extended to time-dependent calculations and compared to an analytical work for a one-dimensional circulating fuel reactor already existing in the literature.

In this decade, the working temperature of the power plants significantly increased to above 700 °C to enhance efficiency. The corrosive species deposits on the hot section components were prone to corrosion damage at elevated temperatures. This study investigates the microstructure and high-temperature corrosion characteristics of the wrought and wire-arc additive manufactured (WAAM) 316L stainless steel in an aggressive molten Na2SO4 + 25% NaCl salt and air environment at 750 °C. The corrosion rate of both wrought and WAAM-built 316L was higher in the molten salt (MS) environment compared to air due to the chloride and sulfate deposits. The wrought 316L was severely prone to corrosion damage with spallation and cracking, which was attributed to the dissolution of the non-protective Fe2O3 scale by Cl. The WAAM-built 316L showed the lower oxidation and depth of corrosion attack in both air and MS environments than the wrought steel due to the fine dendrite grains, resulting in the outward diffusion of more Cr. The accelerated degradation occurred on the WAAM and wrought 316L SS in MS condition due to the dissolution of Cr2O3 and the faster inward diffusion of Na+. The detailed oxide growth, internal corrosion attack, and oxide failure mechanisms of the steels were explored in the air and MS conditions.

This paper considers the necessary conditions for using a derivative of a transient hot-wire (termed a needle probe) approach to measure the thermal conductivity of electrically conducting fluids at high temperatures, especially molten halide salts. The focus is on the development of a new theory based on a multi-layer system necessary to ensure electrical isolation of electrical wires from the surrounding fluid. This includes the use of a thin annulus of fluid to minimize convective heat transfer modes within the fluid of interest, which was inspired by the concentric cylinder method. Good measurements require the following considerations: concentricity of the probe and surrounding crucible to ensure a consistent fluid gap, accounting for corrections for deviation of the model at early times, and modeling radiation heat transfer through transparent fluids. Uncertainties are larger than transient hot-wire methods because of the deviations from experimental conditions that can easily match an analytical approximation. An appropriate estimation of the measurement uncertainty can be obtained through careful design of the instrumentation, thorough uncertainty analysis, and limiting the measurements to only the applicable thermal property ranges of the approach. The 1D model used to interpret measured temperature data has been shown to be reliable for thermal conductivity measurements ranging from at least 0.39 W (mK−1) to 0.92 W (mK−1) and for temperatures from 293 K to 1023 K. The approach is used to present thermal conductivity data of the molten salts NaCl–KCl (51–49 mol%) and LiCl–NaCl (72–28 mol%). [ABSTRACT FROM AUTHOR]

For the rational manipulation of the production quality of high-temperature metallurgical engineering, there are many challenges in understanding the processes involved because of the black box chemical/electrochemical reactors. To overcome this issue, various in-situ characterization methods have been recently developed to analyze the interactions between the composition, microstructure, and solid–liquid interface of high-temperature electrochemical electrodes and molten salts. In this review, recent progress of in-situ high-temperature characterization techniques is discussed to summarize the advances in understanding the processes in metallurgical engineering. In-situ high-temperature technologies and analytical methods mainly include synchrotron X-ray diffraction (s-XRD), laser scanning confocal microscopy, and X-ray computed microtomography (X-ray μ-CT), which are important platforms for analyzing the structure and morphology of the electrodes to reveal the complexity and variability of their interfaces. In addition, laser-induced breakdown spectroscopy, high-temperature Raman spectroscopy, and ultraviolet–visible absorption spectroscopy provide microscale characterizations of the composition and structure of molten salts. More importantly, the combination of X-ray μ-CT and s-XRD techniques enables the investigation of the chemical reaction mechanisms at the two-phase interface. Therefore, these in-situ methods are essential for analyzing the chemical/electrochemical kinetics of high-temperature reaction processes and establishing the theoretical principles for the efficient and stable operation of chemical/electrochemical metallurgical processes. [ABSTRACT FROM AUTHOR]

Molten salts (MSs) thermal energy storage (TES) enables dispatchable solar energy in concentrated solar power (CSP) solar tower plants. CSP plants with TES can store excess thermal energy during periods of high solar radiation and release it when sunlight is unavailable, such as during cloudy periods or at night. This capability allows these plants to provide reliable, dispatchable power, ensuring a continuous electricity supply to the grid. This paper examines the challenges and opportunities of utilizing higher‐temperature molten salt formulations to enhance power cycle efficiency. Drawing on existing literature, performance analysis of existing power plants, and novel simulation results, we project the expected technological improvements by the end of this decade. By using 15 h of TES and a higher temperature MS formulation, with heat transfer fluid hot temperatures of 700°C, and a power cycle 350 bar 700°C of efficiency 48%, the annual electricity production from a 115 MW power plant in Daggett, California is 688 GWh, the total installed cost is $684 m while the 25‐year LCOE is 6.37 c/kWh. [ABSTRACT FROM AUTHOR]

[Display omitted] Silicon (Si) has gained substantial interest as a potential component of lithium-ion battery (LIB) anodes due to its high theoretical specific capacity. However, conventional methods for producing Si for anodes involve expensive metal reductants and stringent reducing environments. This paper describes the development of a calcium hydride (CaH 2)–aluminum chloride (AlCl 3) reduction system that was used for the in-situ low-temperature synthesis of a core–shell structured silicon–carbon (Si–C) material from rice husks (RHs), and the material was denoted RHs-Si@C. Moreover, as an LIB anode, RHs-Si@C exhibited exceptional cycling performance, exemplified by 90.63 % capacity retention at 5 A g−1 over 2000 cycles. Furthermore, the CaH 2 –AlCl 3 reduction system was employed to produce Si nanoparticles (Si NPs) from RHs (R-SiO 2 , where SiO 2 is silica) and from commercial silica (C-SiO 2). The R-SiO 2 -derived Si NPs exhibited a higher residual silicon oxides (SiO x) content than the C-SiO 2 -derived Si NPs. This was advantageous, as there was sufficient SiO x in the R-SiO 2 -derived Si NPs to mitigate the volumetric expansion typically associated with Si NPs, resulting in enhanced cycling performance. Impressively, Si NPs were fabricated on a kilogram scale from C-SiO 2 in a yield of 82 %, underscoring the scalability of the low-temperature reduction technique. [ABSTRACT FROM AUTHOR]

Currently, the properties of molten lithium, sodium and potassium fluoride eutectic mixtures with different additions are immensely important for the development of molten salt nuclear reactors. In the present work, the density of molten FLiNaK mixtures with additions of neodymium fluoride was studied by the Archimedean method. The neodymium fluoride addition increased the density of the 46.5 mol% LiF–11.5 mol % NaF–42.0 mol % KF (FLiNaK) and FLiNaK + 25 mol% NdF3 mixture from 2.00 g⋅cm−3 to 3.25 g⋅cm−3, respectively. Thermal diffusivity was measured by the laser flash method. It was found to decrease abruptly as the NdF3 concentration increased. Thermal conductivity of the FLiNaK–NdF3 system, which was calculated using thermal diffusivity, density and heat capacity values, was lower than that of molten FLiNaK at the same temperature. The composition with 25 mol % NdF3 (0.69 W⋅m−1⋅K−1) had a lower value of thermal conductivity than molten FLiNaK without additions (0.74 W⋅m−1⋅K−1) at the same temperature of at 973 K. It can be concluded that neodymium fluoride additions resulted in the density growth and decrease in the thermal diffusivity, heat capacity and thermal conductivity of molten FLiNaK. The change in the neodymium fluoride concentration can affect the technological process in nuclear reactor. [ABSTRACT FROM AUTHOR]

Abstract Inorganic fillers play an important role in improving the ionic conductivity of solid composite electrolytes (SCEs) for Li‐ion batteries. Among inorganic fillers, perovskite‐type lithium lanthanum titanate (LLTO) stands out for its high bulk Li+ conductivity on the order of 10−3 S cm−1 at room temperature. According to a literature survey, the optimal LLTO filler should possess the following characteristics: i) a single‐crystal structure to minimize grain boundaries; ii) a small particle size to increase the filler/polymer interface area; iii) a 1D morphology for efficient interface channels; and iv) cubic symmetry to facilitate rapid bulk Li+ diffusion within the filler. However, the synthesis of single crystal, 1D LLTO nanomaterials with cubic symmetry is challenging. Herein, a flux strategy is developed to synthesize La0.5M0.5TiO3 (LMTO, M═Li, Na, and K) single‐crystal nanorods with an A‐site‐disordered, cubic perovskite phase. The flux media promotes the oriented growth of nanorods, prevents nanorods from sintering, and provides multiple alkali metal ion doping at M sites to stabilize the cubic phase. SCEs compositing the Li+‐conducting LMTO nanorods as fillers and poly[vinylene carbonate‐co‐lithium sulfonyl(trifluoromethane sulfonyl)imide methacrylate] matrix exhibit more than twice the conductivity of the neat polymer electrolyte (30.6 vs 14.0 µS cm−1 at 303 K).

A rotating basket cathode improved the TiO2-reduction efficiency by 6.5-fold and accelerated the electrolysis of molten CaCl2-CaO at 1173 K in an Ar atmosphere. Promoting dissolution of the CaO byproduct and mass transfer near the cathode was effective for TiO2 reduction and α -Ti deoxidation. The reduction efficiency can be predicted by optimizing the rotational speed and pulse rotation. [ABSTRACT FROM AUTHOR]

Strong metal‐support interaction (SMSI) plays a vital role in tuning the geometric and electronic structures of metal species. Generally, a high‐temperature treatment (>500 °C) in reducing atmosphere is required for constructing SMSI, which may induce the sintering of metal species. Herein, we use molten salts as the reaction media to trigger the formation of high‐intensity SMSI at reduced temperatures. The strong ionic polarization of the molten salt promotes the breakage of Ti−O bonds in the TiO2 support, and hence decreases the energy barrier for the formation of interfacial bonds. Consequently, a high‐intensity SMSI state is achieved in TiO2 supported Ir nanoclusters, evidenced by a large number of Ir−Ti bonds at the interface, at a low temperature of 350 °C. Moreover, this method is applicable for triggering SMSI in various supported metal catalysts with different oxide supports including CeO2 and SnO2. This newly developed SMSI construction methodology opens a new avenue and holds significant potential for engineering advanced supported metal catalysts toward a broad range of applications. [ABSTRACT FROM AUTHOR]

Solar thermal plants typically undergo trough operational cycles spanning between 20 and 25 years, highlighting the critical need for accurate assessments of long-term component evolution. Among these components, the heat storage media (molten salt) is crucial in plant design, as it significantly influences both the thermophysical properties of the working fluid and the corrosion of the steel components in thermal storage systems. Our research focused on evaluating the long-term effects of operating a low-melting-point ternary mixture consisting of 30 wt% LiNO3, 57 wt% KNO3, and 13 wt% NaNO3. The ternary mixture exhibited a melting point of 129 °C and thermal stability above 550 °C. Over 15,000 h, the heat capacity decreased from 1.794 to 1.409 J/g °C. Additionally, saline components such as CaCO3 and MgCO3, as well as lithium oxides (LiO and LiO2), were detected due to the separation of the ternary mixture. A 30,000 h exposure resulted in the formation of Fe2O3 and the presence of Cl, indicating prolonged interaction with the marine environment. This investigation highlights the necessity of analyzing properties under actual operating conditions to accurately predict the lifespan and select the appropriate materials for molten salt-based thermal storage systems. [ABSTRACT FROM AUTHOR]

Ionic liquid materials are viable candidates as a heat transfer fluid (HTF) in a wide range of applications, notably within concentrated solar power (CSP) technology and molten salt reactors (MSRs). For next-generation CSP and MSR technologies that strive for higher power generation efficiency, a HTF with wide liquid phase range and energy storage capabilities is crucial. Studies have shown that eutectic chloride salts exhibit thermal stability at high temperatures, high heat storage capacity, and are less expensive than nitrate and carbonate salts. However, the experimental data needed to fully evaluate the potential of eutectic chloride salts as a HTF contender are scarce and entail large uncertainties. Considering the high cost and potential hazards associated with the experimental methods used to determine the properties of ionic liquids, molecular modeling can be used as a viable alternative resource. In this study, the eutectic ternary chloride salt MgCl2-NaCl-KCl is modeled using ab-initio molecular dynamics simulations (AIMDs) in the liquid phase. Using the simulated data, the thermophysical and transport properties of eutectic chloride salt can be calculated: density, viscosity, heat capacity, diffusion coefficient, and ionic conductivity. For an initial model validation, experimental pair-distribution function data were obtained from X-ray total scattering techniques and compared to the theoretical pair-distribution function. Additionally, theoretical viscosity values are compared to experimental viscosity values for a similar system. The results provide a starting foundation for a MgCl2-NaCl-KCl model that can be extended to predict other fundamental properties. [ABSTRACT FROM AUTHOR]

The paper presents an investigation into the reduction and adsorption performance of hierarchically structured carbon films (HSCFs). The HSCFs are synthesized from glucose using a molten magnesium catalyst under a layer of molten salts during their reaction with an aqueous sodium permanganate solution at pH values from 1 to 14 and temperatures from 20 to 80 °C. By increasing the temperature from 20 to 80 °C, the reduction and adsorption of Mn (VII) on the HSCFs is accelerated by a factor of 150; moreover, the reaction products are not temperature-dependent. According to Raman and photoelectron spectroscopy data, synthesis in the neutral and basic sodium permanganate solutions produces an "HSCF-sodium-manganese spinel" nanocomposite, the greater part (≈ 80%) of whose manganese is in a tetravalent state, while the remainder is in a trivalent state. The predominant precipitation of manganese spinel nanocrystals on the developed side of the carbon film may be related to the full disappearance of the sp hybridized carbon peak on the XPS spectra. It is shown for the first time that the reactivity of carbon varies with its valence state. Of the three hybridized states of carbon, sp hybridized carbon is demonstrated to have the highest reactivity. It is confirmed that 100% reduction and adsorption from 0.01 to 0.1 M sodium permanganate solutions occur in neutral and basic media. The adsorption capacity of the hierarchically structured carbon film interacting with 0.1 M sodium permanganate solution is more than 450 mg/g, representing a high adsorption performance as compared to other carbon nanomaterials investigated earlier. [ABSTRACT FROM AUTHOR]

The materials used in concentrating solar power (CSP) systems are becoming of interest because of the high energy efficiency of energy storage. Molten salts can be used as both heat-storage media and heat-transfer fluid in a CSP system. In molten salts, steel alloys used in vessels and pipelines are highly vulnerable to hot corrosion. To protect steel alloys, applying a coating is an excellent strategy to extend the life of the alloy. NiCrAl coatings are well-suited for high-temperature environments. The purpose of this study was to investigate the corrosion behavior of NiCrAl with Si addition coatings on AISI304 in molten salt. NiCrAl coatings with and without Si addition were deposited using the high-velocity oxygen fuel (HVOF) technique. The corrosion test was performed using an immersion test in modified solar salt with 0.5% NaCl at 400–600 °C. Gravimetric methods evaluate the weight change for immersion tests. At 400 °C, an increased amount of weight gain due to the oxidation reaction and molten salt infiltration was observed. At 600 °C, the corrosion reaction was more dominant, and apparent oxidation was decreased; however, oxidation products NiO and sodium aluminum silicate were detected. Si addition supports the formation of the protective oxide sodium aluminum silicate, which inhibits molten salt oxidation reaction and molten salt infiltration. [ABSTRACT FROM AUTHOR]

For the first time, the mechanism of metal aluminum dissolution in NaF–ScF3 eutectic melts and the chemical interaction between the constituents of this mixture have been thoroughly studied by a combination of differential thermal analysis (DTA), high temperature and solid-state nuclear magnetic resonance (NMR), and X-ray diffraction (XRD) coupled with the molecular dynamic simulations. The formation of an insoluble Al3Sc alloy in molten (NaF–ScF3)eut system was proven, and the chemical mechanism of this aluminothermic Al3Sc alloy production was elucidated. Corresponding ex situ examinations bring to light the formation of NaScF4 and solid solution of Na3(Al,Sc)F6 in cooled bath. The molecular dynamics calculations of the bath allow us to construct the structural model and to predict viscosity, density and electrical conductivity of the reagent melt to help to optimize the conditions of the alloy synthesis. [ABSTRACT FROM AUTHOR]

Solid solutions are garnering substantial attention in the realm of solar energy utilization due to their tunable electronic properties, encompassing band edge positions and charge‐carrier mobilities. In this study, we designed and synthesized Co1‐xZnxFe2xGa2–2xO4 (0

The effects of different molten salts on the corrosion resistance of laser powder bed fusion (L-PBF) 316L stainless steel was evaluated at 650 and 700 °C. The samples were characterized via XRD and SEM/EDX after high-temperature corrosion tests to evaluate the corrosion damage to the L-PBF 316L stainless steel caused by the molten salts. The presence of the salts accelerated the corrosion process, the chloride-based salts being the most aggressive ones, followed by the carbonate-based and the nitrate/nitrite-based salts, respectively. The L-PBF 316L did not react strongly with the nitrate/nitrite-based salts, but some corrosion products not found in the samples tested in the absence of salts, such as NaFeO2, were formed. LiFeO2 and LiCrO2 were identified as the main corrosion products in the samples exposed to the carbonate-based molten salts, due to the high activity of Li ions. Their growth produced the depletion of Fe and Cr elements and the formation of vacancies that acted as diffusion paths on the surface of the steel. In the samples exposed to chloride-based molten salts, the attacked area was much deeper, and the corrosion process followed an active oxidation mechanism in which a chlorine cycle is assumed to have been involved. [ABSTRACT FROM AUTHOR]

In the pursuit of fusion power, achieving tritium self-sufficiency stands as a pivotal challenge. Tritium breeding within molten salts is a critical aspect of next-generation fusion reactors, yet experimental measurements of Tritium Breeding Ratio (TBR) have remained elusive. Here we present the results of the Build A Better Yield blanket experiment, which represents a pioneering effort in tritium research by utilizing high-energy (14 MeV) neutron irradiation of molten salts, a departure from conventional low-energy neutron approaches. Using a small-scale (100 ml) molten salt tritium breeding setup, we not only simulated, but also directly measured a TBR ( $3.57\times 10^{-4}$ ). This innovative approach provides crucial experimental validation, offering insights unattainable through simulation alone. Moreover, our findings reveal a surprising outcome: tritium was predominantly collected as HT, contrary to the expected TF. This underscores the complexity of tritium behavior in molten salts, highlighting the need for further investigation. This work lays the foundation for a more sophisticated experimental setup, including increasing the volume of the breeder, enhancing neutron detection, and refining tritium collection systems. Such improvements are crucial for advancing our understanding of fusion reactor feasibility and paving the way for future experiments.

In the present work, the phase conversion of amorphous calcium phosphate (ACP) in different molten chlorides (LiCl, NaCl, KCl, CaCl 2) was investigated in detail. The main synthesis parameters influencing the phase purity and morphological features of the products include the chemical composition of molten salts, the heat treatment temperature and the ACP-to-flux ratio. The selective synthesis of single-phase Ca 5 (PO 4) 3 Cl or Ca 2 PO 4 Cl depends on the content of CaCl 2 in the reaction medium. The morphology control of Ca 5 (PO 4) 3 Cl powders was achieved by varying the KCl/CaCl 2 ratio in the flux, resulting in the formation of the particles of different size and shape. The KCl-rich fluxes led to the formation of relatively small nearly spherical particles, whereas the CaCl 2 -rich fluxes promoted an anisotropic growth of the Ca 5 (PO 4) 3 Cl crystals resulting in the formation of monodispersed hexagonally-shaped microrods. Whereas the anisotropic growth was observed at relatively low temperature (750 °C) the increase of the reaction temperature up to 1200 °C significantly reduced this effect leading to the formation of the particles with obviously low aspect ratio. The phase crystallinity and purity were analyzed using powder X-ray diffraction, FTIR spectroscopy as well as 31P, 35Cl and 1H solid-state NMR. The morphological features and chemical composition of the synthesized products were studied by SEM/EDX analysis. [ABSTRACT FROM AUTHOR]

A novel ternary eutectic salt, NaNO3-KNO3-Na2SO4 (TMS), was designed and prepared for thermal energy storage (TES) to address the issues of the narrow temperature range and low specific heat of solar salt molten salt. The thermo-physical properties of TMS-2, such as melting point, decomposition temperature, fusion enthalpy, density, viscosity, specific heat capacity and volumetric thermal energy storage capacity (ETES), were determined. Furthermore, a comparison of the thermo-physical properties between commercial solar salt and TMS-2 was carried out. TMS-2 had a melting point 6.5 °C lower and a decomposition temperature 38.93 °C higher than those of solar salt. The use temperature range of TMS molten salt was 45.43 °C larger than that of solar salt, which had been widened about 13.17%. Within the testing temperature range, the average specific heat capacity of TMS-2 (1.69 J·K−1·g−1) was 9.03% higher than that of solar salt (1.55 J·K−1·g−1). TMS-2 also showed higher density, slightly higher viscosity and higher ETES. XRD, FTIR and Raman spectra SEM showed that the composition and structure of the synthesized new molten salt were different, which explained the specific heat capacity increasing. Molecular dynamic (MD) simulation was performed to explore the different macroscopic properties of solar salt and TMS at the molecular level. The MD simulation results suggested that cation–cation and cation–anion interactions became weaker as the temperature increased and the randomness of molecular motion increased, which revealed that the interaction between the cation cluster and anion cluster became loose. The stronger interaction between Na-SO4 cation–anion clusters indicated that TMS-2 molten salt had a higher specific heat capacity than solar salt. The result of the thermal stability analysis indicated that the weight losses of solar salt and TMS-2 at 550 °C were only 27% and 53%, respectively. Both the simulation and experimental study indicated that TMS-2 is a promising candidate fluid for solar power generation systems. [ABSTRACT FROM AUTHOR]

Thermal energy storage (TES) is crucial in bridging the gap between energy demand and supply globally. Concentrated Solar Power (CSP) plants, employing molten salts for thermal storage, stand as an advanced TES technology. However, molten salts have drawbacks like corrosion, solidification at lower temperatures, and high costs. To overcome these limitations, research is focusing on alternative TES materials such as ceramic particles. These solids match molten salts in energy density and can withstand higher temperatures, making them well-suited for CSP systems. This study revolves around subjecting Solar Salt alone and Solar Salt alongside Volcanic Ash (VA) and Electric Arc Furnace Slag (EAFS) to a comprehensive thermal cycling test. This test is designed to assess the compatibility over the thermal cycles of the Solar Salt and the Solar Salt in contact with these solids in a CSP plant with a thermocline configuration. With a final thermal and chemical evaluation, our observations indicate that EAFS and VA demonstrate promising compatibility but an increase in the reduction rate of the Solar Salt due to a catalyst effect from EAFS in contact with the salt. No discernible alterations were detected in the properties of either the solid materials or solar salt when combined. [ABSTRACT FROM AUTHOR]

The successful fabrication is reported of highly crystalline Co nanoparticles interconnected with zeolitic imidazolate framework (ZIF-12) -based amorphous porous carbon using the molten-salt-assisted approach utilizing NaCl. Single crystal diffractometers (XRD), and X-ray photoelectron spectroscopy (XPS) analyses confirm the codoped amorphous carbon structure. Crystallite size was calculated by Scherrer (34 nm) and Williamson-Hall models (42 nm). The magnetic properties of NPCS (N-doped porous carbon sheet) were studied using a vibrating sample magnetometer (VSM). The NPCS has a magnetic saturation (Ms) value of 1.85 emu/g. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that Co/Co3O4 nanoparticles are homogeneously distributed in the carbon matrix. While a low melting point eutectic salt acts as an ionic liquid solvent, ZIF-12, at high temperature, leading cobalt nanoparticles with a trace amount of Co3O4 interconnected by conductive amorphous carbon. In addition, the surface area (89.04 m2/g) and pore architectures of amorphous carbon embedded with Co nanoparticles are created using the molten salt approach. Thanks to this inexpensive and effective method, the optimal composite porous carbon structures were obtained with the strategy using NaCl salt and showed distinct electrochemical performance on electrochemical methodology revealing the analytical profile of Erdatifinib (ERD) as a sensor modifier. The linear response spanned from 0.01 to 7.38 μM, featuring a limit of detection (LOD) of 3.36 nM and a limit of quantification (LOQ) of 11.2 nM. The developed sensor was examined in terms of selectivity, repeatability, and reproducibility. The fabricated electrode was utilized for the quantification of Erdafitinib in urine samples and pharmaceutical dosage forms. This research provides a fresh outlook on the advancements in electrochemical sensor technology concerning the development and detection of anticancer drugs within the realms of medicine and pharmacology. [ABSTRACT FROM AUTHOR]

Tritium is a radioactive isotope of hydrogen, and due to its limited supply and related high price, it is necessary to recover it from tritiated materials via detritiation technologies. The number of tritiated materials arises during fusion. Tritium from fusion reactors is deposited in the outer layer of plasma-facing materials, which must be dealt with during maintenance or decommissioning processes. A second source of waste is laboratory equipment that could be contaminated with tritium. High-temperature treatment in an oxidation environment can achieve the release of tritium from metals or organic materials. The tritiated vapor is then captured in a series of water bubblers and reprocessed into pure T2. One of the high-temperature methods is molten salt oxidation (MSO), which uses high temperatures, alkaline salt, and an oxidative environment for flameless oxidation of different types of waste. This work aimed to simulate the detritiation processes of tritiated organic materials in MSO technology. First, a series of experiments with D2O absorbed in ion resins was conducted. The organic waste was decomposed within the molten salt, and the flue gas was measured to determine the oxidation efficiency. The D2O was captured in a series of water bubblers, and the water was then analyzed with attenuated total reflectance (ATR)–Fourier transform infrared spectroscopy (FTIR). The results showed that all deuterium in the form of D2O was caught in the first water bubbler. The capture efficiency ranged from 22.32% to 61.13%. The lower efficiency capture can be explained as D2O in water can form a HDO molecule and its correct determination is problematic. The second type of experiment was carried out with T2O with an activity of 851 Bq and with tritiated oil with an activity of 2495 Bq. The T2O was added to the set amount of ion resins and dosed into MSO. A peristaltic pump dosed the tritiated oil. The flue gas was measured to determine oxidation efficiency, and the T2O was captured within the water bubblers. The water was analyzed with liquid scintillation spectroscopy. The capture efficiency ranged between 76.42% to 97.87%. The results showed that this technology is suitable for the detritiation of tritiated organic materials. [ABSTRACT FROM AUTHOR]

Abstract—The electrochemical reduction of U(III) ions to the metal in molten LiCl–KCl eutectic in a temperature range of 673–793 K on cadmium and gallium electrodes under an inert gas atmosphere is studied by cyclic voltammetry, square-wave voltammetry, and zero current potentiometry. Reagents containing no traces of moisture, oxygen, and products of their interaction are used in the experiments. All main procedures are carried out in a dry glove box under a purified argon atmosphere. As shown by cyclic and square-wave voltammetry, the cathodic reduction of uranium(III) ions on the active cadmium and gallium electrodes in the "electrochemical window" under study occurs with a depolarization of 0.2–0.4 V and depends on the cathode material. The potential shift to the electropositive range is found to be related to the formation of intermetallic compounds of uranium with the material of the active electrodes. The potentiostatic electrolysis of the melt at the potentials of the current peaks observed on the cyclic voltammograms using the active electrodes is conducted to identify the compositions of the cathodic deposits. The X-ray diffraction (XRD) data show that the intermetallic compound UCd11 is formed on the cadmium electrode and UGa3 and UGa2 are formed on the gallium electrode. SEM image and EDS analysis of the sample surface confirm the presence of fine fragments of the U–Cd and U–Ga intermetallic compounds. The conditions for the formation of alloys of a specified composition are determined by potentiostatic electrolysis. The equilibrium potentials of the U–Cd and U–Ga alloys are measured by zero current potentiometry, and the temperature dependences of the apparent standard potentials of the alloys are calculated. The electrochemical extraction of uranium from the LiCl–KCl–UCl3 melt is studied. The determined degree of extraction of uranium from the electrolyte on the active liquid electrodes at various electrolysis times exceeds 97%. [ABSTRACT FROM AUTHOR]

Intercalation of layered materials offers an effective approach for tunning their structures and generating unprecedented properties. The multiple van der Waals (vdW) gap combined with long‐range ordering guests can change the interaction of layered host materials and electromagnetic field. Herein, a chemical‐scissor intercalation protocol medicated by molten salt is proposed for tailing the electromagnetic properties of transitional metal dichalcogenides (TMDCs). NbS2 is functional intercalated by heteroatoms (Fe, Co, Ni). The intercalated NbS2 with superlattice exhibit improved dielectric properties due to the reduced Brillouin zone size and the local electron distribution. Both the computational and experimental investigations indicate enhanced electron transport and additional polarized centers caused by intercalation. Overall, this work shows the great potential of structure editing of vdW materials, whilst intercalation via the chemical scissor in molten salts is considered a feasible intercalation strategy to further enrich their applications. [ABSTRACT FROM AUTHOR]

Molten salts are the most widely used thermal energy storage system in Concentrated Solar Power (CSP) plants, accounting for 50% of the installed capacity. Many studies have conducted life cycle assessments of the Greenhouse Gas (GHG) emissions produced within the CSP ecosystem; however, it has not yet been standardized for molten salt storage. This study compares GHG emissions of molten salt storage in CSP with conventional coal and natural gas power plants, to measure the environmental impact they can have in the CSP ecosystem. This was achieved with the use of simulations for 48 operational CSP plants worldwide using the system advisor model with their respective operation conditions. Results show that for the three configurations studied, CSP plants would result in annual 3,99 MMtCO2eq of emissions displaced when compared to a coal power plant and 1,61 MMtCO2eq compared to a natural gas power plant.

Enhancing the operational efficiency of parabolic trough solar collector (PTSC) systems is key to the advancement of solar energy technologies that enhance power generation sustainability. In the quest for efficient, environmentally friendly energy sources, solar energy systems have been a major focus of both researchers and industry. Adding hybrid nanoparticles (Al2O3–TiO2) to different base fluids of thermal oil or molten salts and then simulating the PTSC's energetic and exergetic performance is pivotal to efficiency enhancement. The focus of this paper will be on three thermal oils Syltherm-800, Therminol VP-1, and Therminol 75 that are used as base fluids with the addition of hybrid nanoparticles. Molten salts such as Solar Salt, Hitec, and HitecXL, which are considered different base fluid types, are also simulated with the same hybrid nanoparticle combination. The inlet temperature is found to be a determining factor in the choice of the base fluid. Inlet temperatures in the range of 300–650 K for thermal oils with the addition of Al2O3–TiO2 have improved the thermal and exergy efficiency of the PTSC by approximately 0.99 % and 0.59 %, respectively. Therminol VP-1/Al2O3–TiO2 has the highest average thermal efficiency among other thermal oils, with an average percentage of 71.68 %, while Syltherm-800/Al2O3–TiO2 has recorded the highest exergy efficiency of 24.1 %. At higher inlet temperatures above 500 K mixing Al2O3–TiO2 with molten salts has increased both energetic and exergetic PTSC performance by approximately 0.60 %. Solar Salt/Al2O3–TiO2 has the highest average thermal and exergy efficiency of 61.8 % and 36.1 %, respectively.