Thermal Route Research Articles

ZnO nanorods loading with fatty amine as composite PCMs device for efficient light-to-thermal and electro-to-thermal conversion

Phase change materials (PCMs) with ideal light-to-thermal conversion efficiency play an important role in solar energy storage and conversion. Hence, we report the fabrication of a novel composite PCMs (CPCMs) device based on ZnO nanorods deposited indium tin oxide (ITO) glass loading with fatty amines. ZnO nanorods were deposited on the ITO glass using a three-electrode electrodeposition method, and 1-Hexadecylamine (HDA) was loaded on the ITO glass via spin-coating, followed by spraying polypyrrole (ppy) on the surface of CPCM device to improve thermal conductivity and solar absorption. The as-prepared CPCM device exhibits excellent light-to-thermal conversion efficiency, achieving a high conversion efficiency of 90.2% obtained at 1sun owing to its high light absorption (80%), enhanced thermal conductivity (improved by 57.8%), and the unique vertical aligned nanorods structure which could significantly decrease tortuosity, thereby reducing thermal route and lowering thermal response time. Furthermore, the electro-to-thermal conversion efficiency of the CPCMs device has also been investigated and the results show that it can reach up to 69.8% under a low voltage of 5 V, indicating that the CPCM device has a high potential in the field of electro-to-thermal conversion. Based on the benefits listed above, the CPCM device may serve an ideal platform for a wide range of solar energy storage and conversion applications.

Synthesis and characterization of titanium nitride nanoparticles

Titanium nitride (TiN) materials have gained an interest over the past years due to their unique characteristics, such as thermal stability, extreme hardness, low production cost, and comparable optical properties to gold. In the present study, TiN nanoparticles were synthesized via a thermal benzene route to obtain black nanoparticles. Scanning electron microscopy (SEM) was carried out to examine the morphology. Further microscopic characterization was done where the final product was drop cast onto double-sided conductive carbon tape and sputter-coated with gold/palladium at a thickness of 4 nm for characterization by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-Ray spectroscopy (EDS) that revealed they are spherical. ImageJ software was used to measure the average size of the particles to be 79 nm in diameter. EDS was used to determine the elements present in the sample and concluded that there were no impurities. Further characterization by Fourier Transform infrared (FTIR) spectroscopy was carried out to identify the characteristic peaks of TiN. X-ray diffraction (XRD) revealed typical peaks of cubic phase titanium nitride, and crystallite size was determined to be 14 nm using the Debye-Scherrer method. Dynamic light scattering (DLS) analysis revealed the size distribution of the TiN nanoparticles, with nanoparticles averaging at 154 nm in diameter. Zeta potential concluded the surface of the TiN nanoparticles is negatively charged.

Pyrolysis of Sugarcane (Saccharum officinarum L.) Leaves and Characterization of Products.

The finite nature, regional availability, and environmental problems associated with the use of fossil fuels have forced all countries of the world to look for renewable eco-friendly alternatives. Agricultural waste biomasses, generated through the cultivation of cereal and noncereal crops, are being considered renewable and viable alternatives to fossil fuels. In view of this, there has been a global spurt in research efforts for using abundantly available agricultural wastes as feedstocks for obtaining energy and value-added products through biochemical and thermal conversion routes. In the present work, the thermochemical characteristics and thermal degradation behavior of sugarcane leaves (SCL) and tops were studied. The batch pyrolysis was carried out in a fixed-bed tubular reactor to obtain biochar, bio-oil, and pyrolytic gas. Effects of bed height (4–16 cm), particle size (0.180–0.710 mm), heating rate (15–30 °C/min), and temperature (350–650 °C) were investigated. The maximum yields of bio-oil (44.7%), biogas (36.67%), and biochar (36.82%) were obtained at 550, 650, and 350 °C, respectively, for a 16 cm deep bed of particles of size 0.18–0.30 mm at the heating rate of 25 °C/min. The composition of bio-oil was analyzed using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), and gas chromatography–mass spectrometry (GC–MS) techniques. Several aliphatic, aromatic, phenolic, ketonic, and other acidic compounds were found in the bio-oil. The biochar had a highly porous structure and several micronutrients, making it useful as a soil conditioner. In the middle temperature ranges, biogas had more methane and CO and less hydrogen, but at higher temperatures, hydrogen was predominant.

Amorphization and Crystallization of Hexanitroazobenzene (HNAB) Using Conventional DSC and Flash DSC

AbstractThe present work presents results from an investigation of the glass transition and crystallization behaviors of HNAB tested over more than five orders of magnitude of cooling rate from 0.005 °C/s to 600 °C/s (0.3 to 36000 °C/min) by a combination of conventional and Flash differential scanning calorimetry (DSC). The work quantifies the influence of the thermal amorphization route on the properties of this high explosive. Cooling rates faster than 100 °C/s (6000 °C/min) result in amorphous HNAB as expected from prior work, but we also find that amorphization of the HNAB occurs at cooling rates slower than 0.008 °C/s (0.5 °C/min). The behavior of the amorphous HNAB made by slow cooling is compared with that of amorphous HNAB made by fast cooling, as well as with that made by solvent casting in terms of glass transition temperature, apparent activation energy of glass transition, and dynamic fragility parameter m. Besides, the non‐isothermal crystallization response as a function of cooling rate is also reported. The thermal stability and decomposition energy of amorphous HNAB are compared with those of the crystalline counterpart, being similar heats of decomposition of 3295 and 3392 J/g, respectively; suggesting that the amorphous HNAB will have similar thermal stability and chemical energy to the crystalline form.

Light on the origin of the verdete siltstone, Bambuí group, central Minas Gerais state, Brazil

The Verdete is a variety of a greenish siltstone that occurs occasionally at different stratigraphic levels of the Serra da Saudade Formation, Bambuí Group (Neoproterozoic to Cambrian age). The main rock types related to the Verdete are potassium rich and show the follow mineralogy: quartz, illite/glauconite, orthoclase, albite, ilmenite, fluorapatite and dawsonite. Conventionally, the Verdete has been considered as formed by diagenetic processes in transgressive conditions at calm water environments. However, the present research based on different data considers the Verdete as result of potassic metasomatism in preexisting detritic sedimentary rock (siltstone, fine sandstone and greywacke). The main arguments that support the potassic metasomatic alteration hypothesis are: i) coincidence of the Verdete main occurrences with geophysical anomalies interpreted as alkaline intrusions in depth; ii) presence of dawsonite which is one hydrothermal sodium carbonate; iii) local presence of brecciated facies of phosphorite cross cutting the Verdete facies; iv) lateral discontinuity of the beds and v) microscopic evidence of substitution in coarser facies. The potassic fluids percolated in fracture zone in a northeast trend in the main area of occurrence in central Minas Gerais State (Cedro do Abaeté Town), and besides this region there are also incidence in other areas. The Verdete is considered as a possible source of potassium to be applied to agromineral or industrial supply for fertilization production. In this way, the understanding of its origin must be important to develop new processes or improve the methods to the potassium recover (chemical, biological and thermal routes).

Cold-resonance-mediated self-stabilization of Kerr frequency combs in a Si3N4 microring resonator

Kerr frequency combs (KFCs) generated from continuous-wave pumped microresonators have been vastly exploited for a plethora of applications. Along with an appreciable bandwidth, most of the applications demand a stable and coherent frequency comb, which is a challenging quest. Several complex experimental approaches were reported to attain stable frequency combs. In this paper, we report an innovative and simple approach to achieve stabilized KFCs in a ${\text{Si}}_{3}{\text{N}}_{4}$ racetrack microring resonator. Intensive numerical simulations reveal an enhancement of the comb bandwidth when the temperature is reduced slightly lower than the room temperature. The maximum temperature rise due to the propagating dissipative Kerr soliton (DKS) has also been studied through finite element simulations. Through homogeneous steady-state analysis we validate that the stability of a single DKS state is enhanced at the temperatures reported in this paper. We believe that the proposed thermal route may help in reducing the complex experimental procedures for stabilization of KFCs.

New nitrogen-doped graphitic carbon nanosheets with rich structural defects and hierarchical nanopores as efficient metal-free electrocatalysts for oxygen reduction reaction in Zn-Air batteries

Carbon materials are highly promising alternative metal-free catalysts for oxygen reduction reaction (ORR), an important element reaction involved in various energy storage/conversion processes, while controllable and fine structural and morphological tunning is key for maximizing the catalytic performance. Here, we report the rational design of hierarchical porous graphitic carbon nanosheets with rich defects (d-pGCS) based on a facile two-step thermal treatment route, delivering superior catalytic ORR performance in alkaline electrolytes. The second thermal treatment is critical in creating such structural defects and nanopores. Through optimizing synthesis parameters, d-pGCS-1000 exhibits outstanding electrocatalytic ORR performance in terms of positive onset potential (0.95 V), half-wave potential (0.82 V), and limiting current density (6.02 mA cm−2). As a proof-of-concept, the obtained Zn-air battery delivers a large open-circuit voltage (1.42 V), high peak power density (182.8 mW cm−2), high specific capacity (773 mAhgZn−1), and good rate performance. Such results are comparable to or even better than the Pt/C-based Zn-air battery.

Structural and Morphological Analysis of the First Alloy/Dealloy of a Bulk Si-Li System at Elevated Temperature.

There have been tremendous improvements in the field of Si electrode materials, either by nanoscale or composite routes, and though silicon-containing carbon electrode materials have begun to penetrate the marketplace, the commercial capacities achieved by these cells still fall short of the promise of high capacity Si electrodes. Enabling a cheaper feedstock of Si in the bulk form would make this technology more accessible, though there are many challenges that must be overcome. Whereas other methods utilize nanomaterials and composites to overcome volume expansion and pulverization of a Si electrode, this study explores a thermal route to enable the use of carbon-free bulk Si. To accomplish this, a modified Swagelok cell has been constructed to accommodate high temperatures, corrosive molten salt electrolytes, and a molten lithium electrode to study lithiation of a bulk Si wafer at 250 °C. Scanning electron microscopy, X-ray diffraction, and microcomputed tomography were used to examine morphological and structural changes within the Si upon lithiation and delithiation. It was discovered that semiordered LixSi phases were formed upon lithiation in molten LiTFSI electrolyte at 250 °C, and the higher temperature does not completely mitigate pulverization of the bulk Si electrode.

Silicon Carbide Formation in Reactive Silicon-Carbon Multilayers

An alternative low thermal budget silicon carbide syntheses route is presented. The method is based on self-propagating high-temperature synthesis of binary silicon-carbon-based reactive mul­tilayers. With this technique, it is possible to obtain cubic polycrystalline silicon carbide at relatively low annealing temperatures by a solid state reaction. The reaction starts above 600 °C. The transformation process proceeds in a four-step process. The reaction enthalpy was determined to be (-70 ± 4) kJ/mol.

Thermal versus entropic Mpemba effect in molecular gases with nonlinear drag.

Loosely speaking, the Mpemba effect appears when hotter systems cool sooner or, in a more abstract way, when systems further from equilibrium relax faster. In this paper, we investigate the Mpemba effect in a molecular gas with nonlinear drag, both analytically (by employing the tools of kinetic theory) and numerically (direct simulation Monte Carlo of the kinetic equationand event-driven molecular dynamics). The analysis is carried out via two alternative routes, recently considered in the literature: first, the kinetic or thermal route, in which the Mpemba effect is characterized by the crossing of the evolution curves of the kinetic temperature (average kinetic energy), and, second, the stochastic thermodynamics or entropic route, in which the Mpemba effect is characterized by the crossing of the distance to equilibrium in probability space. In general, a nonmutual correspondence between the thermal and entropic Mpemba effects is found, i.e., there may appear the thermal effect without its entropic counterpart or vice versa. Furthermore, a nontrivial overshoot with respect to equilibrium of the thermal relaxation makes it necessary to revise the usual definition of the thermal Mpemba effect, which is shown to be better described in terms of the relaxation of the local equilibrium distribution. Our theoretical framework, which involves an extended Sonine approximation in which not only the excess kurtosis but also the sixth cumulant is retained, gives an excellent account of the behavior observed in simulations.

Reduced graphene oxide supported zinc/cobalt oxide nanoparticles as highly efficient electrocatalyst for oxygen evolution reaction

Developing novel electrocatalysts with both high efficiency and low cost are highly needed for the oxygen evolution reaction (OER). In this work, self-assembled cobalt oxide (Co3O4) and zinc oxide (ZnO) nanoparticles on thermally reduced graphene oxide (TRGO) were successfully synthesized via simple chemical wet, sol–gel, and thermal routes as highly efficient electrocatalysts for the OER in acidic media. The synthesized TRGO@ZnO/Co3O4 catalyst presents improved OER performance, owing to the TRGO, which acted as a conducting support in the synthesized catalyst. The catalyst exhibited a low ovepotential of 160 mV at a current density of 10 mA cm−2 and a small Tafel slope of 50 mV dec-1, which is much smaller than that of pristine Co3O4 and TRGO. The specific activity and turnover frequency of the optimal catalyst at an overpotential of 400 mV were 0.334 mA cm−2 and 2.891 s−1, respectively, which are considerably higher than those of pristine Co3O4 (0.102 mA cm−2, 0.088 s−1) and ZnO/Co3O4 (0.063 mA cm−2, 0.109 s−1). In addition, it exhibited excellent stability and initial catalytic activity remained at 89% after a long time of 50 h at 10 mA cm−2 with faradaic efficiency of 95.34%. Thus, the synthesized TRGO@ZnO/Co3O4 catalyst material can be a promising candidate material to replace the expensive noble metal as an OER catalyst.

Sliding wear behavior of a sustainable Fe-based coating and its damage mechanisms

The current industry demand is to identify suitable alternatives to the risk-of-supply prone and/or toxic, WC-Co and electrolytic hard chrome coatings without comprising the desired wear performance. Therefore, compositions based on abundantly available elements (e.g. ‘Fe’) that possess adequate wear resistance are desirable from health, sustainability and economic standpoints. In this work, crystalline Fe-based (Rockit-401) coatings were processed using two different thermal spray routes, i.e. HVOF and HVAF spraying. The influence of deposition route and processing conditions on the microstructure, porosity content, hardness and phase composition was examined. The as-deposited coatings were subjected to mild (5 N) and harsh (15 N) dry sliding wear test conditions by employing alumina ball as the counter surface material, and their wear performance was examined. Mild sliding wear test conditions (5 N) resulted in anomalous wear behavior, where the abrupt drop in CoF at several instances during the test was observed in all the investigated coatings. On the other hand, under harsh wear test conditions (15 N), such an abrupt dip in CoF was not observed. Detailed wear mechanisms of the coatings were revealed under different test conditions (5 N and 15 N). This work sheds light on processing, wear behavior and wear mechanisms of a sustainable and high-performance coating that fulfills non-toxic and sustainability goals in tandem for tribological applications.

Sheared Edge Formability Characterization of High Strength Aluminum Alloys at Room and Elevated Temperatures using Hole Expansion Tests

High strength 6000- and 7000-series aluminum alloys have significant potential for automotive light weighting due to their high strength-to-weight ratios. Alternate thermal processing routes and warm forming operations with rapid heating to 150 - 300°C are being explored to expand their forming process windows. While the constitutive and formability behavior of these alloys at elevated temperatures is an active area of research, limited data is available on their sheared edge stretchability, particularly under elevated temperature forming conditions. To this end, the influence of cutting clearance on the edge fracture limits of two precipitation hardening alloys, AA6013-T4 and AA7075-T6, and a non-heat treatable AA5182-O were first investigated at room temperature using the conical hole expansion test. A 12% clearance was found to be suitable for the three materials and used to process the hole expansion samples prior to warm forming. Microhardness tests were used to characterize the depth and severity of the shear affected zone (SAZ) for the AA7075-T6 before and after the warm forming cycle. The forming temperature was found to increase the hole expansion ratio by approximately 400%, 150%, and 520% for the AA5182-O, AA6013-T4, and AA7075-T6 respectively relative to the room temperature tests. The edge stretchability during W-temper forming of the AA6013 and AA7075 at room temperature was also assessed. It was observed that W-temper forming negatively influenced the hole expansion of AA6013 by approximately 30% relative to the T4 condition. Conversely, the hole expansion ratio for AA7075 when formed in W-temper increased by over 35% with respect to the T6 temper.

From Low to High Saturation Magnetization in Magnetite Nanoparticles: The Crucial Role of the Molar Ratios Between the Chemicals.

In this study, a comprehensive characterization of iron oxide nanoparticles synthesized by using a simple one-pot thermal decomposition route is presented. In order to obtain monodisperse magnetite nanoparticles with high saturation magnetization, close to the bulk material, the molar ratios between the starting materials (solvents, reducing agents, and surfactants) were varied. Two out of nine conditions investigated in this study resulted in monodisperse iron oxide nanoparticles with high saturation magnetization (90 and 93% of bulk magnetite). The X-ray diffraction analyses along with the inspection of the lattice structure through transmission electron micrographs revealed that the main cause of the reduced magnetization in the other seven samples is likely due to the presence of distortion and microstrain in the particles. Although the thermogravimetric analysis, Raman and Fourier transform infrared spectroscopies confirmed the presence of covalently bonded oleic acid on the surface of all the samples, the particles with higher polydispersity and the lowest surface coating molecules showed the lowest saturation magnetization. Based on the observed results, it could be speculated that the changes in the kinetics of the reactions, induced by varying the molar ratio of the starting chemicals, can lead to the production of the particles with higher polydispersity and/or lattice deformation in their crystal structures. Finally, it was concluded that the experimental conditions for obtaining high-quality iron oxide nanoparticles, particularly the molar ratios and the heating profile, should not be chosen independently; for any specific molar ratio, there may exist a specific heating profile or vice versa. Because this synthetic consideration has rarely been reported in the literature, our results can give insights into the design of iron oxide nanoparticles with high saturation magnetization for different applications.

Liberation and Separation of Valuable Components from LED Modules: Presentation of Two Innovative Approaches

The rapid development of light-emitting-diode (LED) technology is attributed to its superiority over light sources of earlier generations. Although LED lamps, compared to compact fluorescent lamps, are considered less harmful to the environment, there is still no efficient solution to deal with them at the end of their lifecycle. The first part of the study provides a detailed characterisation of LED lamps, focusing on their most interesting component: the LED module. LED packages attached to the module are highly enriched with Ga, In, Pd, Ag, Au, Sr, Y, Ce, Eu, Gd, and Lu, with the content of each element varying greatly depending on the LED technology. In the second part of this research, two new approaches for liberation and concentration of valuable components from LED modules are presented and compared: a chemical route and a thermal route. The chemical treatment leads to a highly selective separation of LED chips and encapsulation. Enrichment factors up to about 125 are achieved, and a concentrate is obtained containing approximately 14 wt% of the aforementioned valuable components. However, the process requires aromatic solvents, which are viewed as toxic. The thermal treatment results in separation of the aluminium heat sink from all other components of the LED module. Enrichment is approximately ten times lower, but the approach is technically feasible.

NO mechanisms of syngas MILD combustion diluted with N2, CO2, and H2O

The NO mechanism under the moderate or intense low-oxygen dilution (MILD) combustion of syngas has not been systematically examined. This paper investigates the NO mechanism in the syngas MILD regime under the dilution of N2, CO2, and H2O through counterflow combustion simulation. The syngas reaction mechanism and the counterflow combustion simulation are comprehensively validated under different CO/H2 ratios and strain rates. The effects of oxygen volume fraction, CO/H2 ratio, pressure, strain rate, and dilution atmosphere are systematically investigated. For all the MILD cases, the contribution of the prompt and NO-reburning routes to the overall NO emission is less than 0.1% due to the lack of CH4 in fuel. At atmospheric pressure, the thermal route only accounts for less than 20% of the total NO emission because of the low reaction temperature. Moreover, at atmospheric pressure, the contribution of the NNH route to NO emission is always larger than 55% in the N2 atmosphere. The N2O-intermediate route is enhanced in CO2 and H2O atmospheres due to the increased third-body effects of CO2 and H2O through the reaction N2 + O (+M) ↔ N2O (+M). Especially in the H2O atmosphere, the N2O-intermediate route contributes to 60% NO at most. NO production is reduced with increasing CO/H2 ratio or pressure, mainly due to decreased NO formation from the NNH route. Importantly, a high reaction temperature and low NO emission are simultaneously achieved at high pressure. To minimize NO emission, the reactions should be operated at high values of CO/H2 ratios (i.e., >4) and pressures (e.g., P > 10 atm), low oxygen volume fractions (e.g., XO2 < 15%), and using H2O as a diluent. This study provides a new fundamental understanding of the NO mechanism of syngas MILD combustion in N2, CO2, and H2O atmospheres.

Dilution effects analysis on NOx emissions of opposed-jet H2/CO syngas diffusion flames

Syngas is a promising alternative fuel for stationary power generation due to cleaner combustion than convectional fossil fuels. During the gasification processes, the by-products of CO2, H2O, or N2 may be present in the syngas mixture to control the flame temperature and emissions. Several studies indicated that syngas with dilutions is capable of reducing pollutant emissions such as NOx emissions. This work applied a numerical model of opposed-jet diffusion fames to explore the dilution effects on NOx formation and differentiate the inert effect, thermal/diffusion effect, chemical effect, and radiation effect from CO2, H2O, or N2 dilutions. The numerical study was performed by a revised OPPDIF program coupling with narrowband radiation model and detail chemical mechanism. The dilution effects on NOx formation were analyzed by comparing the realistic and hypothetical cases. Regardless the diluent types, the inert effect is the main cause to reduce NO production, followed by chemical effect and radiation effect. The thermal/diffusion effect may promote NO formation because the preferential diffusion due to different diffusivities between diluents and syngas magnifies the reaction rate locally. CO2 dilution reduces NO by radiation effect at low strain rate, and contributes NO reduction by chemical effect at high strain rate. At the same dilution percentage, CO2 dilution reduces NO production the most, followed by H2O and N2. Besides the thermal/diffusion effect, the chemical effect of H2O enhances NO production through thermal route and reburn route.

Thermal runaway routes of large-format lithium-sulfur pouch cell batteries

<h2>Summary</h2> Lithium-sulfur (Li-S) batteries emerge as one of the most attractive energy storage systems due to their ultra-high theoretical energy densities, but the pace of their thermal safety assessment is obviously lagging behind. Herein, by investigating the thermal runaway behavior of Li-S pouch cells from the materials level, we unprecedentedly revealed that the thermal runaway route starts from cathode-induced reactions and then gets accelerated by reactions from the anode. Besides, the solvent vaporization is verified to dominate pressure building up during thermal runaway. Moreover, Li-S batteries employing varied electrolytes with different thermal stabilities, even inorganic all solid-state electrolytes, all undergo rapid thermal runaway at a narrow temperature range due to the intrinsic thermal features of the sulfur cathode and Li metal anode sublimating, melting, and cross-reacting at high temperatures. The in-depth depicted thermal runaway routes will deliver great inspiration for mitigating the safety issues of next generation batteries.

Thermal and photocatalytic cascade one-pot synthesis of secondary amine using multifunctional Pd decorated MOF-derived CeO2

The use of a single catalyst to perform thermal and photochemical N-alkylation of amine is challenging work. Herein, Pd decorated MOF-derived CeO2 was prepared for the cascade one-pot synthesis of secondary amine by thermal and photocatalytic routes. Among the designed catalysts, Pd(0.5%)/CeO2-300 exhibited the best activity for thermal and photocatalytic one-pot secondary amine synthesis involving benzyl alcohol and aniline. The physicochemical characteristics of Pd(0.5%)/CeO2-300 suited for the oxidation of benzyl alcohol followed by condensation with aniline to form an imine. Further, reduction of imine over Pd NPs decorated on CeO2-300 took place to form secondary amine. An excellent conversion of benzyl alcohol and secondary amine selectivity was observed thermally at 100 °C in 26 h. The Pd(0.5%)/CeO2-300 exhibited excellent activity in white LED. Interestingly, more activity was achieved in sunlight. The Pd(0.5%)/CeO2-300 demonstrated excellent stability under thermal and photocatalytic conditions and was recycled 5 times without losing any significant activity. The surface area, acidity, and elemental compositions were characterized by various physicochemical techniques. The light absorption property, bandgap, charge carrier separation, and photocurrent measurements were carried out by photoelectrochemical and optoelectronic analysis. The reaction mechanism and structural activity relationship correlated with control experiments, catalytic activity data, physicochemical, and optoelectronic characterization. One catalyst affording efficient activity in conventional thermal and photocatalytic conditions, especially sunlight, would be exciting to researchers and industrial practitioners.

Thermal plasma synthesized nano-powders of (LaCe)B6 starting from oxide-based precursors and its field electron emission performance

High temperature synthesis process of microcrystalline and nanocrystalline (LaCe)B6 using Self-propagating High temperature Synthesis (SHS) and arc plasma gas phase condensation methods, respectively have been investigated. These methods are rapid and economically viable processes used for the synthesis of technologically important refractory hexaborides. Microcrystalline powders of (LaCe)B6 were synthesized using the SHS process, starting from oxide precursors of lanthanum, cerium, and boron. The powders obtained using SHS process were used as a precursor to getting nanocrystalline (LaCe)B6 using the thermal plasma route. The thermal plasma synthesis was carried out using nitrogen and argon plasmas, respectively. In-situ plasma diagnostics were used to identify evaporated species and determine plasma temperature during the formation of nanocrystalline (LaCe)B6 using optical emission spectroscopy. Further, an effect of plasma input parameters on the structural and optical properties of as synthesized nanocrystalline (LaCe)6 were investigated using XRD analysis, Raman spectroscopy, and X-ray photoelectron spectroscopy. A thorough investigation of morphological and structural properties of synthesized nanocrystalline (LaCe)6 was carried out using transmission electron microscopy. Finally, field effect electron emission properties of the microcrystalline and nanocrystalline product were investigated and current density, turn on field, stability of emission performance were determined.