Long-term Thermal Stability Research Articles

Degradation Behaviors of NPB Molecules upon Prolonged Exposure to Various Thermal Stresses under High Vacuum below 10-4 Pa.

Understanding of the long-term thermal stabilities of organic light-emitting diode (OLED) materials during film deposition is important to accurately identifying their processing windows. The thermal stresses imposed on OLED materials in the evaporation source during the deposition process may cause phase transition and/or degradation of the source materials, which results in variations in their purity and thermal properties, such as the vapor pressure and, ultimately, the device degradation. In this work, we designed a simple and efficient apparatus to determine the long-term thermal stability of OLED materials, which allows prolonged heating of a minimal amount of the sample (∼2 g) for 50 h even under high vacuum below 10–4 Pa where the organic powder samples easily and rapidly vaporized because of exposure to temperature above their deposition temperature. We used this apparatus to evaluate the thermal degradation behaviors of N,N′-bis(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB), which is a widely used hole-transporting material in OLEDs, upon prolonged exposure to various thermal stresses. After prolonged heating at 330 °C (380 °C) for 25 h (50 h), the change in purity, mass, vapor pressure, and phase of the heated NPB were analyzed by high-performance liquid chromatography, liquid chromatography–mass spectrometry, thermogravimetric analysis, and X-ray diffraction. The lifetime of OLEDs using the heated NPB was measured to study how the thermally induced material degradation affects the device characteristics. The results showed that the NPB degradation caused by prolonged exposure to 330 °C accelerated over time. In addition, it was confirmed that the degradation products with high molecular weight that form due to exposure to 380 °C was the main cause of device degradation.

A Liquid Arylazopyrazole Derivative as Molecular Solar Thermal Fuel with Long-term Thermal Stability

A liquid arylazopyrazole derivative is newly synthesized as molecular solar thermal fuel. It shows efficient trans-to-cis photoisomerization in the neat liquid state, with the cis-isomer having a s...

Thermal charge/discharge performance of iron–germanium alloys as phase change materials for solar latent heat storage at high temperatures

In this study, an iron–germanium alloy (Fe–Ge alloy) was examined as a phase change material at temperatures exceeding 800°C for thermal energy storage in solar thermal applications. The cyclic properties of the thermal charge/discharge of the Fe–Ge alloy were examined at various thermal cycles. A thermal reliability test was performed in the form of a multi-cyclic performance assessment to evaluate the short- and long-term thermal stability of this alloy. Eutectic and hypereutectic chemical compositions of the Fe–Ge alloy were placed in a graphite container under vacuum and an inert atmosphere. The Fe–Ge alloy was experimentally examined for its compatibility with the container material of graphite-carbon. The element distribution of each Fe–Ge alloy was examined via a cyclic performance test. The heat storage capacities were evaluated and compared with those of chloride molten salts. The Fe–Ge alloy exhibits significant potential as a latent heat storage material in next-generation solar thermal applications as it demonstrates various advantages, namely: a higher storage capacity than that of chloride molten salts, temperature followability to the phase diagram, a quick thermal response, satisfactory cyclic behavior of charge/discharge modes, a thermodynamically stable metallographic structure, and non-reactivity with capsulation materials of graphite carbon.

Optimizing the α1B-adrenergic receptor for solution NMR studies

Sample preparation for NMR studies of G protein-coupled receptors faces special requirements: Proteins need to be stable for prolonged measurements at elevated temperatures, they should ideally be uniformly labeled with the stable isotopes 13C, 15N, and all carbon-bound protons should be replaced by deuterons. In addition, certain NMR experiments require protonated methyl groups in the presence of a perdeuterated background. All these requirements are most easily satisfied when using Escherichia coli as the expression host. Here we describe a workflow, starting from a temperature-stabilized mutant of the α1B-adrenergic receptor, obtained using the CHESS methodology, into an even more stable species, in which flexible parts from termini were removed and the intracellular loop 3 (ICL3) was stabilized against proteolytic cleavage. The yield after purification corresponds to 1–2 mg/L of D2O culture. The final purification step is ligand-affinity chromatography to ensure that only well-folded ligand-binding protein is isolated. Proper selection of detergent has a remarkable influence on the quality of NMR spectra. All optimization steps of sequence and detergent are monitored on a small scale by monitoring the melting temperature and long-term thermal stability to allow for screening of many conditions. The stabilized mutant of the α1B-adrenergic receptor was additionally incorporated in nanodiscs, but displayed slightly inferior spectra compared to a sample in detergent micelles. Finally, both [15N,1H]- as well as [13C,1H]-HSQC spectra are shown highlighting the high quality of the final NMR sample. Importantly, the quality of [13C,1H]-HSQC spectra indicates that the so prepared receptor could be used for studying side-chain dynamics.

Highly efficient catalytic oxidation of benzene over Ag assisted Co3O4 catalysts

Ag supported on Co3O4 catalysts were prepared by facile one-pot solvotermal method. The obtained Ag/Co3O4 catalysts exhibited the excellent catalytic activity of benzene oxidation in comparison with Ag/Co3O4-I catalyst synthesized by the impregnation method. The characterization results revealed that Ag/Co3O4 catalysts possessed more surface active oxygen species and lattice defects, and exhibited the excellent low-temperature reducibility. The catalytic activity of benzene oxidation was in the order of 2%Ag/Co3O4 > 1%Ag/Co3O4 > 2%Ag/Co3O4-I > Co3O4. Accordingly, 2%Ag/Co3O4 catalyst exhibited the T50 and T90 values of 181 and 201 °C for benzene oxidation, which were lower than those of other catalysts. In addition, the catalysts exhibit the outstanding long-term thermal stability.

Exploratory Experimental Study on the Mechanical Properties of Granite Subjected to Cyclic Temperature and Uniaxial Stress

This paper investigates the variation of mechanical properties of granite during temperature and stress cycling, which is an important part of evaluating the long-term thermal and mechanical stability of thermal energy storage. Cyclic temperature and loading tests were conducted where the upper limit of cyclic temperature was 100–600 °C, and the upper stress limits were 70% and 85% of the average uniaxial compressive strength (UCS) at the corresponding temperature. The response of stress–strain characteristics of the granite samples to changes in temperature, and cyclic load upper limit, while the number of temperature and loading cycles was comprehensively analyzed. The results show that the temperature and stress cycles have significant effects on the mechanical properties of granite (i.e., stress–strain curve, strength, elastic modulus, and deformation). The elastic modulus of the sample during loading increases gradually. The strain corresponding to the upper loads of the granite samples decreases with an increasing number of cycles. Additionally, the UCS of samples after 10 cycles at 70% loading stress is greater than that at 85% loading stress. The mechanical properties of samples change dramatically during the first and second cycles at 85% loading stress, whereas at 70% loading stress, the mechanical properties change gradually in the first few cycles, and then tend to stabilize. Cyclic hardening is observed at temperatures below 500 °C, where post cyclic UCS is greater than the uncycled average UCS. This phenomenon requires further research.

Temperature resistance of AM/AMPS/NVP copolymer microspheres

Functional monomers, such as 2-acrylamide-2-methylpropionic sulfonic acid (AMPS), N-vinylpyrrolidone (NVP), and acrylamide (AM), were copolymerized into terpolymer microspheres by inverse suspension polymerization. The structure, morphology, swelling, and temperature resistance of the microspheres were comprehensively characterized through several means, including a 13C nuclear magnetic resonance spectroscope, scanning electron microscope, optical microscope, and laser particle size analyzer (LPSA). The results showed that the AM, AMPS, and NVP monomers were initially polymerized to form smooth and uniformly dispersed terpolymer microspheres. The particle size distribution of the microspheres ranged from 60 to 90 μm at a stirring speed of 300 rpm. The microspheres fully absorbed water and swelled to 21.9 times at 120 °C compared with dry powder microspheres. The ternary copolymer microsphere/water dispersion system can only withstand a 120 °C temperature for 19 days. However, this temperature resistance of the microspheres can be effectively improved by adding the appropriate stabilizer solution. The microspheres can be stabilized for at least 42 days and 120 days in 0.1% thiourea--cobalt chloride composite stabilizer solution and 0.025% LY stabilizer solution, respectively, at 120 °C. It can be seen that the microspheres, water, and stabilizer systems have excellent long-term thermal stability. The AM/AMPS/NVP microspheres with temperature resistance will have broad application prospects in high-temperature reservoirs.

Pentaerythritol stearate ester-based tin (II) metal alkoxides: A tri-functional organotin as poly (vinyl chloride) thermal stabilizers

In this work, a non-volatile solid organotin thermal stabilizer, pentaerythritol stearate ester-based tin (II) metal alkoxides (PSE-Sn) was synthesized with a very simple process and its impact on the thermal stability and processing performance of PVC was evaluated by conductivity measurement, thermal aging, thermogravimetric analysis, and torque rheometer test. The results showed that the addition of PSE-Sn not only could significantly enhance the thermal stability of PVC, accelerate plasticization, but also improve lubrication performance during PVC processing. Thus, PSE-Sn played the role of tri-functional additives: thermal stabilizer, plasticizer, and lubricant. The joint effects of PSE-Sn with ZnSt2 and CaSt2 on the thermal stability of PVC were also evaluated. Results indicate that there is a good synergistic effect between PSE-Sn and ZnSt2 on the initial color and long-term thermal stability of PVC. However, such synergistic effect was not observed between PSE-Sn and CaSt2. In addition, the working mechanism of PVC stabilization by PSE-Sn was also explored. Furthermore, the thermal stability and processing performance of PSE-Sn and methyl tin mercaptide (MTM) on PVC were comparatively tested. PVC stabilized by MTM possessed the longest color stability. The addition of PSE-Sn could also improve the initial color stability and long-term thermal stability of PVC significantly. The results of tensile test showed that both PSE-Sn and MTM could reduce the average tensile strength of PVC but increase the average elongation at break of PVC.

A comprehensive micro scale study of poly-ionic liquid for application in enhanced oil recovery: Synthesis, characterization and evaluation of physicochemical properties

Ionic liquids (ILs) have found their application as novel green surfactants in different chemical industries. These ILs are emerging as a substitute for the surfactants employed in petroleum industries. The quest for a reliable surface-active agent for enhanced oil recovery application has led to the investigation of polymeric ionic liquid as chemical agents. Poly-ionic liquids (PILs) are unique compounds that possess distinctive properties of ILs such as, thermal stability and salt tolerance, along with the specific property of polymers such as flexibility and durability of the polymeric backbone. In present work, poly [1-hexadecyl-3-vinyl-imidazolium bromide] (poly [C16VIm+][Br−]) was synthesized and investigated as a chemical agent for enhanced oil recovery. The interaction of PIL with aqueous injection fluids and crude oil has been analyzed by different properties such as interfacial tension, wettability alteration, dynamic light scattering (DLS), and rheological parameters, which help in understanding the performance of PIL flooding. Surface tensiometry studies revealed the critical micellar concentration (CMC) of PIL to be much lower (200 ppm) in comparison to analogous ILs. The synthesized poly-ionic liquid showed good salt tolerance behavior (>10%) and long-term thermal stability (90 °C) in the presence of monovalent and divalent ions, thus confirming its applicability in the high saline reservoir. Highly beneficial low interfacial tension (IFT) values were obtained at crude oil-aqueous interfaces, which further decreased with an increase in salinity and temperature. DLS studies revealed that hydrodynamic particle size of PIL at CMC to be ~180 nm and it increased with concentration due to aggregation of molecules. PIL showed pseudoplastic or shear-thinning behavior, and viscosity increased with concentration due to the formation of transient network and entanglement of molecules. Contact angle studies showed that poly [C16VIm+][Br−] aqueous solution alters the wetting characteristics of rock from intermediate-wet to water-wet condition (below 20°). Analyzing the above properties, core-flooding experiments were conducted, and additional oil recovery of 31.25% of the original oil in place was obtained after the conventional water flooding.

Recent progress of all-polymer solar cells – From chemical structure and device physics to photovoltaic performance

Single junction organic solar cells (OSCs) have now achieved power conversion efficiencies (PCEs) exceeding 17 %. Most of these high performance OSCs contain fullerene acceptors (FAs) and non-fullerene small-molecule acceptors (NFSMAs). In contrast, there are very limited usages of polymer acceptors. Recently, there are escalating recognition among perylene-diimide/naphthalene-diimide (PDI/NDI) and B⟵N-unit n-type polymers as electron acceptors in the all-polymer solar cells. FAs like PC71BM suffer from multiple limitations. They include restricted energy level tuning, weak absorptions in visible region, narrow spectral breadth, and morphological instability. In contrast to FAs, NFSMAs offer numerous advantages. They include strong and broad absorption in the visible and even the NIR region, tunable energy levels, and simple synthesis and purification procedures. Despite these advantages, the long-term device stability and large-area roll-to-roll (R2R) fabrication remain the major issues for the commercialization for NFSMA-based OSCs. All-polymer solar cells, on the other hand, largely address the problems of device stability and large-area film processing. Many all-polymer solar cells have been demonstrated to possess long-term thermal, photo and mechanical stability. Meanwhile, the precursor solutions for all-polymer solar cells enjoy superior control in the solution viscosity, which is an important factor for the solution processing of large-scale OSCs. Before 2015, all-polymer solar cells received little attention due to their disappointing device performance. Afterwards, PCEs of all-polymer solar cells are picking up. Currently, the best cells have achieved PCEs in excess of 11 %. Here, we provide a systematic review on the evolution of n-type polymeric acceptors used in OSCs. In addition, we summarize the morphological and charge carrier transport properties of all-polymer solar cells and compare with their small molecule acceptor counterparts. The outstanding properties of all-polymer solar cells are discussed from the perspectives of morphology and electron transport in bulk heterojunctions (BHJs). The concept of electron percolation in all-polymer BHJs is introduced and correlated with the excellent device stability. This review should have a broad appeal and enable researchers in comprehending the achievements, challenges, and future directions of all-polymer solar cells.

High-efficiency ternary nonfullerene organic solar cells with record long-term thermal stability

ITC6-2F as a third component in OSCs helps “freeze” the film morphology, leading to significantly improved long-term thermal stability.

Enhanced thermal stability of inverted perovskite solar cells by interface modification and additive strategy.

Inverted perovskite solar cells (PSCs) have recently gained increasing attention because of the long operation lifetime achieved. However, bathocuproine (BCP): a commonly used buffer layer in inverted PSCs, is experimentally confirmed by us to show fast aggregation at the temperature of 85 °C, which is the protocol temperature required by the International Electrotechnical Commission (IEC) standard. This thermal instability of the BCP interfacial layer makes long-term thermal stability of inverted PSCs questionable. Simply removing or replacing it can directly lead to an inferior PCE of a device. We solve this problem by removing the BCP layer and simultaneously increasing the thickness of C60, which obtains a high efficiency of 18% comparable with the device with BCP. This is possibly attributed to the extended migration path of carriers from C60 to metal electrode Ag, consequently reducing the carrier accumulation at the interface. In addition to the interfacial modification, the addition of ionic liquid: BMIMBF4 into perovskite can further improve a device's thermal stability by its effective suppression of perovskite decomposition. The devices with 0.4 mol% of BMIMBF4 exhibit promising thermal stability by retaining 80% of their initial PCE after thermal aging of 400 h at 85 °C.

Construction of Core-Shell Nanowire Arrays in a Cu-Cu2O Film Electrode for High Efficiency in Heat Dissipation.

Thermal engineering dramatically impacts the efficiency of microelectronics, but the corresponding technology lags far behind the need. For energy-efficient thermal management, a Cu-Cu2O film with highly ordered core-shell nanowire arrays and a good self-protection property was successfully fabricated using the magnetron sputtering method. The dense arrangement of nanowires in the films enhances the electronic transport property (220 mΩ sq-1), while the modified stable Cu2O layer maintained its perfect heat dissipation property, along with long-term thermal stability. The core-shell and nanogaps structure imparted an anisotropic thermal conductivity, where the out-plane electronic thermal conductivity (321 ± 16 W m-1 K-1) was 33.6 times higher than the in-plane value. To study the role of anisotropic properties in heat dissipation, a boiling experiment and thermal simulation were undertaken. The Cu-Cu2O core-shell electrode was beneficial to elevate the heat transfer coefficient, which would cause a fast directional transport and reduction of interfacial superheating. We demonstrated that an advancement of microelectronics could be achieved by integrating Cu electrodes with an ordered architecture.

Role of Ionic Headgroups on the Thermal, Rheological, and Foaming Properties of Novel Betaine-Based Polyoxyethylene Zwitterionic Surfactants for Enhanced Oil Recovery

Long-term thermal stability of surfactants under harsh reservoir conditions is one of the main challenges for surfactant injection. Most of the commercially available surfactants thermally degrade or precipitate when exposed to high-temperature and high-salinity conditions. In this work, we designed and synthesized three novel betaine-based polyoxyethylene zwitterionic surfactants containing different head groups (carboxybetaine, sulfobetaine, and hydroxysulfobetaine) and bearing an unsaturated tail. The impact of the surfactant head group on the long-term thermal stability, foam stability, and surfactant–polymer interactions were examined. The thermal stability of the surfactants was assessed by monitoring the structural changes when exposed at high temperature (90 °C) for three months using 1H-NMR, 13C-NMR, and FTIR analysis. All surfactants were found thermally stable regardless of the headgroup and no structural changes were evidenced. The surfactant–polymer interactions were dominant in deionized water. However, in seawater, the surfactant addition had no effect on the rheological properties. Similarly, changing the headgroup of polyoxyethylene zwitterionic surfactants had no major effect on the foamability and foam stability. The findings of the present study reveal that the betaine-based polyoxyethylene zwitterionic surfactant can be a good choice for enhanced oil recovery application and the nature of the headgroup has no major impact on the thermal, rheological, and foaming properties of the surfactant in typical harsh reservoir conditions (high salinity, high temperature).

Low contact resistivity and long-term thermal stability of Nb0.8Ti0.2FeSb/Ti thermoelectric junction

Although half-Heusler compounds are quite promising for thermoelectric power generation, there is only limited research on the interfacial structure between metal electrode and half-Heusler compounds for device applications. This work reports on the characteristics of Nb0.8Ti0.2FeSb/Ti junction and its evolution behavior during 973 K. The Nb0.8Ti0.2FeSb/Ti interface consists of one Ti0.9Fe0.1 layer and one Fe-poor layer. There is an Ohmic contact and a low contact resistivity (0.15 μΩ cm−2) in this junction, on account of the matching of working functions between Nb0.8Ti0.2FeSb and Ti0.9Fe0.1 interlayer. The high doping of Ti high carrier concentration in NbFeSb matrix leads to a high carrier concentration, which results in inducing a large tunneling current at this interface. After aging treatment at 973 K, the Fe-poor layer and the Ti0.9Fe0.1 layer continues to expand, resulting in the increase of the thickness of the interfacial layer and the contact resistivity. The interfacial electrical is only 1.9 μΩ cm−2 after 25 days’ aging. The thickness of the interface layer has a good linear relation with the square root of aging time, which firmly indicates that the growth of the layer is determined by mutual diffusion of Fe and Ti atoms across the interface. The low contract resistivity and long-time thermal stability demonstrate the great potential of Nb0.8Ti0.2FeSb/Ti thermoelectric junction in high efficiency half-Heusler TE devices.

Long-term thermal stability of NPB molecule under high-vacuum

Abstract During the deposition of organic light emitting diodes (OLEDs) using thermal evaporation, the purity of the deposition-source materials varies due to thermal stress, resulting in a reduced device stability. We developed an apparatus to evaluate the long-term thermal stability of deposition-source materials used in OLEDs, which is applicable even under high-vacuum conditions (below 10−4 Pa) where the materials under test run out very quickly when exposed to temperature greater than 300 °C, which is above their deposition temperature. The goal of this work is to understand how thermal stresses imposed on OLED materials for a certain duration affect the material purity and, ultimately, the device performance. We used this apparatus to expose N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB), a commonly used hole-transport material for OLEDs, to thermal stresses for various durations. After maintaining the samples at 330 °C (380 °C) for 25 h (50 h), we performed high-performance liquid chromatography to analyze the material purity. In addition, OLEDs with a simple bilayer structure (NPB/tris(8-hydroxyquinoline)aluminum, Alq3) were fabricated from the heated samples to investigate how material impurities that are induced by thermal stresses affect the device stability. The results show that slight changes in the NPB purity caused by prolonged exposure to high temperatures significantly influence the electrical and optical characteristics of OLEDs fabricated from the heated NPB.

Effect of Boron on the Thermal Stability of the Precipitate Phase of FC92B and FC92N Steels During Aging and Creep

In this study, precipitation strengthening alloying elements (C, N, V, Nb, Ta) and solution strengthening alloying elements (Cr, W, Mo, B) were appropriately combined to fabricate FC92B and FC92N alloys. Long-term aging heat treatments at 650 °C of up to 20,000 h were conducted to compare the high-temperature properties of each alloy, investigate the effects of microstructure stability on creep performance characteristics, and analyze the precipitate growth behavior in relation to the long-term thermal stability of the precipitate phase. Transmission electron microscopy and nanoscale secondary ion mass spectrometry were carried out to investigate microstructural changes according to the aging treatment time and the microstructure of creep specimens in relation to the addition of trace alloying elements. Although FC92B contains a higher B content than FC92N, FC92B did not exhibit significant changes in hardness or tensile strength regardless of the aging time, which extended to a maximum of 20,000 h. The FC92B alloy with an adequate addition of B showed the highest creep performance and exhibited rupture durations that were more than twice those of FC92N under stress conditions of 100 MPa and 140 MPa at 650 °C. The precipitate size of FC92N was significantly coarser than that of FC92B. In FC92B aged for 20,000 h, B was distributed in the grain boundaries, as shown by Nano-Secondary Ion Mass Spectrometry. B content was found to be high within the M23C6 precipitate.

Isoconversional kinetic analysis of thermal decomposition of 1-butyl-3-methylimidazolium hexafluorophosphate under inert nitrogen and oxidative air atmospheres

Non-isothermal decomposition of 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6) in inert nitrogen and air atmospheres was investigated by means of multiple heating-rate thermogravimetric analysis. The results obtained under the heating rates of 5–20 K min−1 show that the [bmim]PF6 pyrolysis mainly occurred from 600 to 800 K and its oxidative thermal decomposition mainly from 550 to 750 K. Kinetic thermal decomposition processes have been analyzed with differential Friedman method and three integral Flynn–Wall–Ozawa, Coats–Redfern and Vyazovkin–Dollimore methods. Through these model-free isoconversional methods, the activation energy and pre-exponential factor over the entire conversion range have been successfully estimated. By using the Coats–Redfern method, the diffusion-controlled D5 model is found to be the best reaction mechanism function for describing two-stage pyrolysis and one-stage oxidative thermal decomposition and leads to very satisfactory calculation performances. The short-term stability and long-term thermal stability are discussed as well.

Biomimetic metal-organic frameworks mediated hybrid multi-enzyme mimic for tandem catalysis

The combination of chemo- and enzyme catalysis for multi-step tandem reactions has presented great challenges for decades. Herein, glucose oxidase (GOx) and a metal-organic framework MOF-545(Fe), which possessed peroxidase-like activity, were combined to construct a mimic multi-enzyme system for tandem catalysis. MOF-545(Fe) not only served as a support for the enzyme immobilization, but also contributed its catalytic activity to co-operate with natural enzymes for the cascade reactions. Based on the prepared mimic multi-enzyme system GOx@MOF-545(Fe), a colorimetric biosensor for glucose rapid detection was achieved with a low limit of detection (0.28 μM) and high specificity. Meanwhile, due to the protection of MOF-545(Fe), the immobilized enzyme exhibited excellent reusability and stability, e.g. long-term stability, thermal stability and anti-organic solvent stability. After being stored at room temperature for 7 days, the immobilized enzyme retained 92% of activity, while only 40% of activity of free enzyme was retained. And the immobilized enzyme maintained 71% of its initial activity after 5 cycles. This strategy of combining MOF mimics and natural enzymes for tandem catalysis may provide a novel and facile approach to design a highly efficient, stable, functional chemo-enzyme composites catalyst, which holds great promise for applications in biosensing, biopharmaceutical and industrial catalysis.

Binary mixtures of fatty alcohols and fatty acid esters as novel solid‐liquid phase change materials

The discovery of new eutectic phase change materials (PCMs) will overcome the current PCM challenges such as nonbiodegradability, super-cooling, and limited thermal stability. This paper reports on the development of new bio-based PCMs composed of binary mixtures of fatty acid esters and fatty alcohols at their eutectic compositions, which provide potential solid-liquid PCMs for building applications. Six binary systems, namely 1-dodecanol (DD) + methyl stearate (MES), DD + methyl palmitate (MEP), DD + methyl laurate (MEL), 1-tetradecanol (TD) + MES, TD + MEP, and TD + MEL were prepared and their thermal behaviours were deliberated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), long-term thermal stability test, and mass loss analysis. Amongst the studied systems, phase change transition temperature and latent heat of fusion of the eutectic mixtures of DD-MES, DD-MEP, TD-MES, and TD-MEP were found to be suitable for the building application with values of 22.46°C/201.91 J/g, 20.34°C/224.45 J/g, 32.05°C/209.38 J/g, and 26.72°C/210.15 J/g, respectively. The average degree of super-cooling for all PCMs was below 2°C, and no significant changes in thermophysical properties of the developed PCMs were observed after 1000 thermal cycles.