Synthesis and Investigation on Nano Enhancement of Novel Margaric Acid-Stearic Acid Eutectic PCM with 1D Carbonaceous Nanoparticles

Phase change materials have gained significant attention in thermal energy storage technology, especially in solar thermal energy systems, because of their high energy storage capacity and broad temperature range of operation. This study develops and synthesise a novel Margaric acid—Stearic acid binary eutectic PCM which was investigated for its the thermophysical properties and chemical characteristics. Margaric acid- Stearic acid eutectic mixture had a weight composition of 64:36 and had a melting temperature at 66.03 °C with a latent heat of fusion 181.85 J/g. Prepared eutectic mixture was chemically stable and did not exhibit thermal degradation up to 200 °C. Carbonaceous nanoparticles were added at three different concentrations intending to triumph over the inherent low thermal conductivity of organic fatty acid components. Nano doping could achieve a highly favourable 9.7% increment in the latent heat of fusion measuring at 199.43 J/g and 130% increase in the thermal conductivity measuring at 0.352 W/mK, which would significantly contribute towards the thermal energy storage and retrieval characteristics of the PCM. The constituents and nanoparticles only developed a physical interaction between them and were chemically stable. The microstructural characteristics and surface morphology was studied through SEM analysis. The optical absorbance characteristics was drastically enhanced by nano doping. The synthesized eutectic mixtures demonstrated thermal stability at temperatures significantly higher than their melting point and maintained their thermal properties and chemical stability even after 500 accelerated thermal cycles.