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The current paper summarizes the development of nano‐enhanced phase change materials (NPCMs) using capric acid (CA) and manganese dioxide (α‐MnO2) nanoparticles. The nanoparticles were obtained by the green synthesis technique using the leaves of Ficus retusa plant. The obtained nanoparticles were used in 1%, 2%, and 3% weight fractions in the nano‐formulations. The field‐emission scanning electron microscopy (FESEM) was employed to confirm the morphological structure and energy‐dispersive X‐ray (EDX) spectroscopy was used for the elemental analysis of the synthesized nanoparticles. The crystallographic studies were done using X‐ray diffraction (XRD) spectroscopy. The Fourier‐transform infrared (FT‐IR) spectroscopy results showed that the insertion of nanoparticles did not disturb the chemical configuration of CA. The differential scanning calorimetry (DSC) analysis revealed that the developed nanocomposites had excellent thermal energy storage capability that lay within the range of 145–164 kJ/kg. Five hundred extended thermal cycles were carried out which showed that the developed PCM had excellent thermal reliability and can be useful for a year‐long application. The variations reported with 1% nano‐formulation was −1.43% to +0.53%, −0.03% to +1.52%, and −6.67% to 9.94% with respect to onset, peak melting temperature, and latent heat of fusion. The thermal gravimetric analysis (TGA) results showed that developed PCMs were stable within the working temperature range. The melting/solidification curve showed faster heat storage and release rates owing to the increased thermal conductivity. These developed PCMs are useful for photovoltaic/thermal and building applications. [ABSTRACT FROM AUTHOR]

Phase change materials have been overwhelmingly used for thermal energy storage applications. Among organics, fatty acids are an important constituent of latent heat storage. Most of the saturated fatty acid PCMs so far studied are either unary or binary constituents of pure fatty acids. In the present study, ternary blends of saturated fatty acids i.e., capric, lauric, myristic, stearic, and palmitic acids have been developed with different weight proportions. A series of 28 ternary blends viz. CA-LA-MA, CA-LA-PA, CA-LA-SA, CA-MA-PA, CA-MA-SA, and CA-PA-SA were prepared and analyzed with differential scanning calorimetry, thermal gravimetric analysis, and Fourier transform infrared spectroscopy. DSC analysis revealed that the prepared materials lie in the 15–30 °C temperature range. Also, 300 thermal melt/freeze cycles were conducted which showed ±10% variation in terms of the melting peak for most of the PCMs, with the average latent heat of fusion between 130 and 170 kJ/kg. The TGA analysis showed that most of the PCMs are thermally stable up to 100 °C and useful for medium-low storage applications, and FTIR analysis showed that the materials are chemically stable after repeated thermal cycles. Based on cycle test performances, the developed materials were found to be reliable for long-term use in building and photovoltaic applications. [ABSTRACT FROM AUTHOR]

The existing study concerned with the development and characterization of ternary eutectics prepared from medium‐chain fatty acids and long‐chain fatty acids. The acids used to prepare these blendings were commercial‐grade capric acid (CA), myristic acid (MA), stearic acid (SA), lauric acid (LA), and palmitic acid (PA). The different ternary groups using these acids were prepared, that is, CA‐LA‐MA, CA‐LA‐PA, CA‐LA‐SA, CA‐MA‐PA, CA‐MA‐SA, and CA‐PA‐SA having variable weight's compositions (90/5/5, 80/10/10, 70/15/15, 60/20/20, 50/25/25, 40/30/30, 30/35/35, 20/40/40, and 10/45/45). The various thermophysical properties such as melting temperature (MT) and latent heat of fusion (LHF) were measured calorimetrically using the differential scanning calorimeter. The MT obtained were in the range of 15°C‐50°C along with adequate LHF values, that is, 80‐200 kJ/kg, which are within the application range of different thermal systems. The various proportions of CA used in the blending have a decisive influence on determining the MT of the concerned ternary concoction. The data from the result authenticate that these developed materials can be useful for thermal regulation of buildings, photovoltaic, space, and solar water heating systems because of their enormous latent heat values and appropriate phase transition temperature. [ABSTRACT FROM AUTHOR]