Thermogravimetric Analysis System Research Articles

The influence of magnetic particle incorporation on bisphenol A removal by β-cyclodextrin-derived sorbent

A novel, biomass-derived hybrid sorbent Ban-CD-EPI-Fe was successfully synthesized in a coprecipitation method, in which β-cyclodextrin copolymerized with banana peel extract and epichlorohydrin was grafted onto an iron oxide surface. The composition, presence of functional groups, morphology, thermal stability, and magnetic properties of the obtained material were characterized by Powder X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Thermogravimetric Analysis (TGA), and Physical Properties Measurement System (PPMS). The material bearing around 28% of β-cyclodextrin units has mesoporous structure with plate-like morphology and active surface area determined by BET and Langmuir models equal to 38.35 and 53.59 m2 g−1, respectively. The sorption studies aimed to remove an endocrine disruptor – bisphenol A (BPA), from water. The results showed that the time evolution could be fitted with pseudo-second kinetic order with a rate constant k equal to 0.05 g mg−1 min−1. According to the Langmuir isotherm, a monolayer is created during BPA sorption, and the maximum sorption capacity was estimated as 93.5 mg g−1. After BPA sorption, the hybrid material could be easily separated by an external magnet and regenerated under mild conditions keeping its recyclability in at least eight cycles.

An investigation of the reaction of metallic uranium with oxygen/nitrogen gas mixtures

The effects of variations in oxygen content as a mixed oxygen/nitrogen gas on the exothermic reaction of uranium were investigated in this work. Samples of metallic uranium with various specific surface areas and masses were reacted in a thermogravimetric analysis system at temperatures ranging between 323 K and 1273 K using gas mixtures 10%, 5%, 1%, or 0.5% oxygen in nitrogen. From the results it was concluded that the minimum oxygen content necessary for the onset of ignition is correlated to the specific surface area of the metallic uranium. The higher the specific surface area, the lower the percentage of oxygen is needed to trigger an ignition event. Within the experimental parameters evaluated here, ignition does not appear to occur for any specific surface area investigated below 1% oxygen content.

Catalytic co-pyrolysis of cellulose over alkali and alkaline earth metal salts for levoglucosan production

A comprehensive study of alkali and alkaline earth metal (AAEM) salts including two different anions (Cl- and CH3COO-) in the catalytic pyrolysis of cellulose to produce levoglucosan (LG), bio-oil, and biochar were investigated. At the same time, the catalytic pyrolysis mechanism was also speculated. The thermogravimetric analyzer (TGA) and lab-scale fixed-bed reactor system were used to determine the thermal degradation process and the pyrolysis products of LG, bio-oil, and biochar. The optimized pyrolysis parameters were obtained by using Box-Behnken design-response surface method. According to the results, AAEM salts significantly boosted the yield of biochar, as well as greatly cut down the output of LG and bio-oil. The rank of effect on LG yield was as follows: CaCl2, MgCl2 > CH3COOK, CH3COONa > (CH3COO)2Mg, (CH3COO)2Ca > KCl, NaCl. Moreover, the addition of AAEM salts considerably dropped the activation energy E of cellulose pyrolysis as well as prompted microcrystalline cellulose pyrolysis under lower temperatures. This study was pivotal in deducing the pathway of cellulose pyrolysis, thereby offering critical insights to hasten the progress of biomass utilization.

Investigation of Pyrolysis Kinetic Triplet, Thermodynamics, Product Characteristics and Reaction Mechanism of Waste Cooking Oil Biodiesel under the Influence of Copper Slag

WCO-Biodiesel can be used as a fuel instead of fossil energy for the copper smelting industry will not only save resources but also protect the environment. The pyrolysis of WCO-Biodiesel in the melting pool is influenced to some extent by the copper slag (CS) generated during the copper smelting process. In this study, the effects of CS on the kinetic triplet, thermodynamics, product characteristics and reaction mechanism of WCO-Biodiesel are comprehensively investigated via a thermogravimetric analyzer and pyrolysis experimental system. Firstly, the apparent activation energy (Eα) is calculated using STR, and Eα decreased at different α under the influence of CS. Then, the trend of the WCO-Biodiesel pyrolysis mechanism with α is determined by the master plots method based on 18 commonly used models similar to the Pn and D1 models. The analysis of WCO-Biodiesel pyrolysis gas products shows that more flammable gases containing H are formed under the influence of CS. The analysis of the liquid products shows that more PAHs and more small molecule products are generated under the influence of CS. Two coke products are produced at high temperatures, which differ significantly in microscopic morphology, spherical carbon particle size and chemical structure. Finally, the mechanism of pyrolysis of the main components in WCO-Biodiesel in the high-temperature environment of melt pool melting is explored.

An investigation of the reaction of uranium with nitrogen - A thermogravimetric analysis study

In this work, the heating corrosion reaction of uranium with dry air and with dry nitrogen gas was investigated. Metallic uranium samples of different specific surface area and mass were reacted in a thermogravimetric analysis system at temperature ramping from 323 K to 1273 K at 15 K.min−1. Ignition was achieved during all heating profiles of the samples reacting with air, with the reported ignition temperature decreasing with increasing specific surface area. Heating cycles were conducted for the uranium and dry nitrogen gas system to investigate if ignition could be attained. These experiments were conducted by varying the specific surface area, sample mass, initial oxide thickness, nitrogen flow rate, and heating ramp rate. None of these experiments showed signs of clear ignition under dry nitrogen. It is hence suggested that uranium ignition under a dry nitrogen atmosphere is not readily attainable and would require a combination of extreme conditions, such as high heating ramp rate for a non-oxidised sample of high surface area and mass.

The effects of heat treatment temperatures on photocatalytic activity of cobalt ferrite nanoparticles synthesised by microwave‐assisted combustion method

AbstractIn this study, the effects on the photocatalytic activities of particles after heat treatment has been applied to cobalt ferrite nanoparticles produced by microwave‐assisted combustion method were observed. The heat treatment applied to the samples was produced with only the microwave effect, at temperatures ranging from 300 to 1000°C. Thermogravimetric analysis was performed on the precursor sample in air atmosphere. During this analysis, the gases released up to 1200°C were identified with a Fourier‐transform infrared (FTIR) spectrometer integrated into a thermogravimetric analysis system. Then, the cobalt ferrite nanoparticles produced with heat treatments applied at various temperatures were used as a photocatalyst to remove the dyestuff content in synthetic wastewaters prepared by using Astrazon Red GTL textile dye by photocatalytic oxidation, and their photocatalytic activities were compared. In these experiments, the operational parameters for photocatalysis processes were applied as 400 rpm for stirring speed, 50 mg/L for initial contaminant concentration, 0.5 g/L for catalyst dosage, 25°C for temperature, and 4400 μW/cm2 for light intensity. As a result of the experiments, it was observed that the crystal structure of the cobalt ferrite nanoparticles produced with the increase of the applied heat treatment temperature improved significantly. The obtained data show a strong relationship between the structural properties of materials and their photocatalytic activities. In addition, it was determined that the dyestuff in the solution was completely degraded in the experiments, and it was determined that all processes were compatible with the pseudo‐first‐order kinetic model.

Thermal behavior, synergistic effect and thermodynamic parameter evaluations of biomass/plastics co–pyrolysis in a concentrating photothermal TGA

The heating rate would significantly impact the pyrolysis process, especially for the reactions containing synergistic effects between two different feedstocks. Co-pyrolysis of two widely available biomass (CC–corncob and PS–peanut shell) with plastic (PET–polyethylene terephthalate and PVC–polyvinyl chloride) was studied in a concentrating photothermal thermogravimetric analysis (CP-TGA) system at three heating rates (100, 500, 1000℃/min). The TG and DTG curves of CC and PS differ due to their polymeric components (holocellulose and lignin); two pronounced levels at 100 and 500 ℃/min heating rates were present in PVC. With increasing heating rate, the lateral shift towards higher temperature regions in the TG and DTG curves exceeded 100 °C. The synergistic effects on the blend samples were concentrated in the main decomposition region (250–580℃) due to rapid volatiles release, and the discrepancy values further stabilized at the final decomposition stages. The activation energy (Ea) was assessed using a comparative study of isoconversional methods, namely Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Starink. The isoconversional methods demonstrated that the co-pyrolysis process required about 30 % less activation energy than the pyrolysis of plastic (PET/PVC) alone. Coats-Redfern's (CR) model-fitting approach was used to identify the kinetic triplet of the devolatilization stage. The CR models revealed that biomass–PET blends belong to two to four-dimensional diffusion models, whereas biomass–PVC blends are dominated by chemical reactions of 1.5 and 2 orders. The energy barrier between activation energy (Ea) and change in enthalpy (ΔH) for all the blend samples was lower (∼5–6 kJmol−1), which slightly increased at higher heating rate.

The Effect of Chemical Activating Agent on the Properties of Activated Carbon from Sago Waste

The effect of chemical activators on the properties of activated carbon from sago waste was conducted in this study by using ZnCl2, H3PO4, KOH, and KMnO4 chemical solutions. The carbonized sago waste was added to each chemical solution, boiled at 85 °C for 4 h, and heated at 600 °C for 3 h. The porosity, microstructural, proximate, and surface chemistry analyses were carried out using nitrogen adsorption with employing the Brunauer Emmett Teller (BET) method and the Barret-Joyner-Halenda (BJH) calculation, scanning electron microscopy by using energy dispersive spectroscopy, X-ray diffractometer, simultaneous thermogravimetric analysis system, and the Fourier-transform infrared spectroscopy. The results showed that the activated carbon prepared using ZnCl2 acid had the highest specific surface area of 546.61 m2/g, while the KOH activating agent surpassed other chemicals in terms of a refined structure and morphology, with the lowest ash content of 10.90%. The surface chemistry study revealed that ZnCl2 and KOH activated carbon showed phenol and carboxylate groups. Hence, ZnCl2 acid was suggested as activating agents for micropore carbon, while KOH was favorable to producing a mesopore-activated carbon from sago waste.

Preparation and study magnetic properties of the nanosized ferrite Zn0.5Mn0.5Fe1.95Mo0.02Tb0.01Sm0.01Gd0.01O4 with negative magnetization. A new result

ABSTRACT This work, concern the studies of the local atomic structure of the rare-earth doped Zn-Mn ferrite (Zn0.5Mn0.5Fe1.95Mo0.02Tb0.01Sm0.01Gd0.01O4), characterization techniques such as thermogravimetric analysis, X-ray diffraction (XRD), and Magnetic Properties Measurement System (MPMS), allowed us the effect of rare earth and their impacts on the structure, the size of nanocrystals, and the magnetic properties of the formed nano-ferrite. The XRD analysis showed that a single-phase was obtained at a low temperature of 500°C, with an environmentally friendly process, and nanometric size (8 nm). Magnetic measurements show a superparamagnetic behavior at 80 and 300 K and a week ferrimagnetism at 5 K. Furthermore, these measurements showed that this sample exhibits negative magnetization under zero-field cooled measurements (ZFC) with a low applied field (100 Oe), while the magnetization remains positive under field-cooled (FC) measurement conditions for the same applied field, which is a new result never observed in the case of Zn-Mn doped nano-ferrite.

Fabrication of recoverable magnetic surface ion-imprinted polymer based on graphene oxide for fast and selective removal of lead ions from aqueous solution

In this study, a novel Pb(II) ion-imprinted polymer based on magnetic laminar graphene oxide composite materials (MnFe2O4@SiO2/GO-IIP) was synthesized by surface ion-imprinted technique for the selective removal of lead ions from aqueous solutions. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and magnetic measurement system were used to characterize the structure and property of as-prepared adsorbents. The adsorption experiments exhibited the MnFe2O4@SiO2/GO-IIP possessed a good adsorption performance and the maximum adsorption capacity of Pb (II) ions reached 58.82 mg g-1. The adsorption could be accomplished within 30 min and the adsorbents could be separated quickly by a permanent magnet. The Langmuir adsorption isotherm and pseudo-second-order kinetic models were used to describe the adsorption procedure appropriately and the result proved that the chemisorption was the rate-limiting step. The selectivity coefficient of Pb (II)/Ni(II), Pb (II)/Zn(II), Pb (II)/Cd(II), Pb (II)/Co(II) were 25.37, 19.71, 33.07 and 45.7, respectively. In addition, the regeneration experiments confirmed the high stability and reproducibility of adsorbents. Lastly, X-ray photoelectron spectroscopy (XPS) proved the bonding mechanisms of the material and Pb(II) ions with a coordination N‒Pb bond.

Effect of 2-phenoxyethanol pre-treatment on structure and adhesion properties of thermotropic liquid crystal polyarylate fibers

This study investigated the surface modification of thermotropic liquid crystal polyarylate (TLCP) fibers by 2-phenoxyethanol pre-treatment, specifically, whether it enhanced their interfacial adhesive properties. The surface chemical compositions and microstructures of both control and 2-phenoxyethanol pre-treated TLCP fibers were characterized by X-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy. Furthermore, thermal, dyeing, and adhesion properties of both control and 2-phenoxyethanol pre-treated fibers were compared by thermogravimetric analysis, colorimetry, and universal material testing system, respectively. The results indicated that 2-phenoxyethanol pre-treatment increased the surface-anchored oxygen atom amount: the oxygen to carbon atomic ratio at the surface of the TLCP fibers increased from 0.17 to 0.22. However, 2-phenoxyethanol pre-treatment showed almost no effect on the thermal stability and mechanical properties of the TLCP fibers. The peeling strength of the 2-phenoxyethanol pre-treated TLCP fabric was around twice that of the control TLCP fabric.

Effects of MgCl2 and Mg(NO3)2 loading on catalytic pyrolysis of sawdust for bio-oil and MgO-impregnated biochar production

For high-quality utilization of biomass resources, co-production of bio-oil and MgO-impregnated biochar from catalytic pyrolysis of Mg-loaded biomass samples is a prospective approach. In this study, the effects of MgCl2 and Mg(NO3)2 loading on catalytic pyrolysis of sawdust for production of high value-added bio-oil and biochar, as well as the catalytic pyrolysis process mechanism were explored. The thermal degradation process behavior and the pyrolysis products of non-condensable gas, bio-oil and biochar were obtained by thermogravimetric analyzer (TGA) and lab-scale fixed-bed reactor system. The product properties were analyzed and characterized by gas chromatography (GC), gas chromatography-mass spectrometry (GCMS), N2 adsorption-desorption, X-rays diffraction (XRD) and transmission electron microscopy (TEM). The obtained results indicated that the loading of Mg salts favored the thermal degradation process of catalytic pyrolysis due to the weakened hydrogen-bonding networks and disrupted the crystalline structures. The enhanced cross-linking and repolymerization reactions of pyrolysis intermediates by the catalytic effect of Mg resulted in the increased non-condensable gas and biochar yields and the decrease of bio-oil yield. The loading of Mg salts also resulted in the decreased CO yield and increased CO2 yield. The relative contents of ketones and furans increased, and the relative contents of phenols and sugars decreased for Mg-loaded SD samples in bio-oil. In addition, the Mg salts loading also favored the formation of developed pore structure and uniformly dispersed MgO nanoparticles in obtained biochar. In general, catalytic pyrolysis of MgCl2-loaded or Mg(NO3)2-loaded sawdust is a feasible method to obtain high value-added bio-oil and MgO-impregnated biochar products.

Nano-carbides as accelerants for boron oxidation reaction

Nano-materials are potential substitutes for micro-sized solid propellant ingredients for improving energy density and reaction activity. So far, several nano-carbides act as accelerants for boron (B) oxidation reaction but their promotive effects and corresponding action mechanisms have rarely been reported. In this work, four nano-carbides [nano-boron carbide (nB4C), nano-titanium carbide (nTiC), nano-zirconium carbide (nZrC), and nano-silicon carbide (nSiC)] were evaluated by thermogravimetric differential scanning calorimetry-combined thermal analysis system and thermodynamic software FactSage 6.2. Among the four nano-carbides, nTiC ranked as the best accelerant by reducing the initial oxidation temperature of B by 10.7% and increasing heat release by 16.0%. By comparison, nB4C and nZrC were ranked as second and third best accelerants with abilities of decreasing the initial oxidation temperature (by 5.4% and 3.3%, respectively) and raising heat release (both by 6.2%). On the other hand, though nSiC slightly decreases the initial oxidation temperature of B, heat release of B + nSiC was lower than that of original B. The action mechanisms of nano-carbides were found complex, and one nano-carbide can accelerate B oxidation following one or several approaches. First, the nano-carbide can be oxidized before B to offer extra heat and induce the oxidation of B. The produced gaseous oxidation product CO2 by nano-carbide may then help break down the liquid oxide film deposited on B particle surface. Third, the reaction between nano-carbide and B would generate borides, which may diminish accumulated liquid oxide film at low temperatures. Finally, the corresponding oxide will be produced to catalyze the oxidation of B. Overall, these findings look promising for future performance improvement of B-based solid propellants.

Growth Kinetics and Characterization of Chromia Scales Formed on Ni–30Cr Alloy in Impure Argon at 700 °C

The oxidation of a Ni–30Cr alloy at 700 °C in impure argon was studied in order to provide new elements of understanding on chromia scale growth in low oxygen partial pressure atmosphere (10−5 atm). Oxidation tests were carried out during 30 min to 50 h in a thermogravimetric analysis system using a symmetrical balance with in situ monitoring of the oxygen partial pressure. The oxidation kinetics were determined as parabolic with an estimated stationary parabolic constant value of 10−15 cm2 s−1, after a transient stage of about 3 h. The oxide scale was identified as a pure chromia layer by TEM and XPS characterisations. After 50 h at 700 °C, the scale thickness estimated by TEM cross section observation was about 100 nm. A slightly thicker and more porous oxide scale was observed above the alloy’s grain boundaries. The metal/oxide interface also exhibited a deeper recession towards the substrate above the alloy’s grain boundaries. The orientation of chromia grains was determined by TKD (transmission Kikuchi diffraction). A strong preference was noted for the orientation perpendicular to the surface, along the direction of the corundum structure. Finally, the type of semiconduction was determined for the scales formed after 7 h and 50 h of oxidation. For the shorter oxidation time, the chromia scale exhibited an n-type semiconduction, whereas for the longer exposure, both n-type and insulating semiconduction were identified.

Isothermal relaxation kinetics for the reduction and oxidation of SrFeO3 based perovskites.

The perovskite oxide SrFeO3 has favourable redox properties for oxygen exchange applications, including oxygen separation and oxygen production chemical looping cycles. For such applications, lower temperature operation can improve the energy demand and feasibility of the process, but can also lead to kinetic limitations. Here we investigate the oxidation and reduction reaction kinetics of SrFeO3 in the temperature range 450-750 K. Isothermal relaxation techniques are used to observe the reaction rates across this temperature range, using a thermogravimetric analysis system. Experimental data are analysed according to an isoconversional method and fit with a simple power law model to extract activation energies. The apparent activation energy of oxidation and reduction was found to be 92 ± 16 and 144 ± 17 kJ mol-1 respectively. Comparison of oxidation and reduction kinetics together with considerations of particle size indicate that the oxidation reaction rate may be limited by diffusion in the bulk, while the reduction reaction rate is limited by the surface reaction. Furthermore, we also investigated the mixed perovskite Sr0.93Ca0.07Fe0.9Co0.1O3, which exhibited a 4-fold increase in the oxidation rate.

DEVELOPMENTOF READY-MADECLOTHING PRODUCTS WITH ROSEMARY OIL TO USE IN AROMATHERAPY

In this study, rosemary oil was obtained from Rosmarinus officinalis L. by water vapor distillation method. Microcapsules were formed in different shell and core ratio using gelatin, gum arabic and ethyl cellulose was employed as shell. Morphological features of the obtained microparticles were examined by scanning electron microscopy (SEM). The bonding structures of microparticles were investigated by using Fourier transformed infrared (FT-IR) spectrometry and thermogravimetric analysis and differential thermal analysis system (DT/TGA). The selected microcapsule formulation was transferred to the fabrics used in sports and leisure garments according to the exhaustion method. The fabrics were examined by SEM for the presence of capsules on the fabrics

A New Approach for Desert Reservoir Exploration: Terahertz Prospecting

An accurate, nondestructive, and economic prospecting technique is of utmost significance to explore petroleum resources in desert, however, the typically used technologies fail to provide direct and noninvasive detection. Here, we demonstrated a terahertz (THz) prospecting method for predicting the distribution of oil reservoir by extracting the sands from the surface areas in a desert oilfield. The accuracy of THz prospecting reached to more than 80%. The trace organic matters migrating from underground reservoir to surface sands can be detected by THz spectroscopy, which was the mechanism of THz spectroscopy for reservoir exploration. The long-chain alkanes, nitro organics, and aromatic compounds were also confirmed by thermogravimetric analysis system coupled with Fourier transform infrared and mass spectroscopy. When the trace organics were decomposed from sands, the THz response was equivalent to that of other sands. Consequently, the petroleum prospecting method on the basis of THz spectroscopy is useful for the improvement and optimization of geophysical exploration system in desert.

Growth, characterization and vibrational spectroscopy of (NH4)2NixMn(1−x)(SO4)2.6H2O:Nd crystals

In this work, mixed crystals of the Tutton’s salt family with empirical formula (NH4)2NixMn(1−x)(SO4)2.6H2O were synthesized with partial occupation of Ni, Mn and doped with Nd, in different stoichiometric fractions employing slow evaporation of the solvent technique. The crystal decomposition processes were analyzed with the help of thermogravimetric analysis system coupled to an FT-IR spectrometer. Dehydration gases H2O and other gases, such as SO3 and NH3 resulting from the degradation of SO4 and NH4 molecules, have been identified, whose presence in the crystalline structure was confirmed by Raman spectroscopy and FT-MIR in the ATR mode. Normal vibrational modes of the octahedral complexes of [X(H2O)6] and residual oxides resulting from TG analysis, were also investigated with the help of Raman spectroscopy. X-ray powder diffraction revealed the crystallinity of the samples. The presence of Ni and Mn were confirmed employing EDS spectroscopy and the quantification of Ni, Mn and Nd in the crystal was determined using ICP-MS technique.

Isothermal Reduction Kinetics and Mechanism of Pre-oxidized Ilmenite

The reduction process of pre-oxidized ilmenite concentrate powder in 30%CO–70%N2 atmosphere was characterized by thermogravimetric and differential thermogravimetric (TG-DTG) analysis system at the temperature from 1073 to1223 K. The isothermal reduction results show that the reduction process is divided into three stages and the corresponding apparent activation energies are obtained by iso-conversional method and model-fitting method, respectively. For the first stage, the conversion degree increases sharply with increasing time, and the reduction process is controlled by the random nucleation and subsequent growth model (A2 model). For the second stage, the conversion degree increases slowly with increasing time, and the reduction process is controlled by the diffusion of carbon monoxide in the reduced layer (D1 model). For the third stage, the reduction processes at different temperatures are controlled by the diffusion of carbon monoxide in the reduced layer (1073 K and D1 model), phase boundary chemical reaction (1123 K and R2 model), random nucleation and subsequent growth (1173 to 1223 K, A2, and A3 models), respectively. For the whole reduction process, the apparent activation energies obtained by iso-conversional method and model-fitting method are 71.72 and 31.92 kJ mol−1, respectively.

Form-stable electrospun nanofibrous mats as a potential phase change material

A series of Poly vinyl butyral–Poly (acrylic acid) (PVB-PAA) based form-stable phase change materials (PCMs) have been prepared for the use of thermal energy storage applications. Six types of formulations containing five different fatty alcohols were prepared by adding PVB to PAA. Using electrospinning to fabricate nanofibrous mats, our aim was to investigate their properties as form-stable PCMs. Fatty alcohols, 1-Tetradecanol, 1-Hexadecanol, 1-Octadecanol, 1-Eicosanol and 1-Docosanol, were added separately to base formulation. The structural characterization tests were performed by ATR-FTIR spectroscopy. Morphological tests were conducted using Scanning Electron Microscope (SEM). Thermal performances and phase change behaviors were tested by thermogravimetric analysis system (TGA) and differential scanning calorimetry (DSC). The heating cycle phase change enthalpy is measured between 223 and 241 J/g, and the freezing cycle phase change enthalpy is found between 215 and 239 J/g. The main decomposition PVB-PAA based PCMs started at 220 °C. This study suggested that PVB-PAA based PCMs possess well phase change properties and they were found to have an applicable temperature range. With the presented results these materials promise a great potential in thermal energy storage applications.