Thermophysical characterization and chemical stability of Ag ₂ O-enhanced eutectic nano-PCMs for moderate-temperature applications

Abstract Thermal energy storage utilizing phase change materials (PCMs) is important for conserving energy because of its high latent heat capacity and ability to maintain a steady temperature during the phase change. However, no single organic PCM provides all of the required qualities, such as ideal melting temperature and latent heat, to perform effectively under specified environmental circumstances. To address this, binary eutectic PCMs are prepared by mixing two or more organic PCMs and optimizing their thermophysical properties. Despite these advancements, their low thermal conductivity remains an issue, limiting overall performance. This study focuses on developing nano-enhanced eutectic phase change material consisting of 64 wt% myristic acid and 36 wt% stearic acid, further improved by incorporating Ag 2 O nanoparticles at concentrations of 0.3–3.0 wt%. Dispersion of nanoparticles within composite phase change material was testified by FTIR and XRD analyses. However, thermal conductivity of the eutectic PCM was significantly enhanced up to 105 % at an equivalent loading of 3.0 wt% nanoparticles. Thermal aging tests also showed thermochemical stability for both pure and composite PCMs in the case of 1,000 cycles. This paper concludes that nano-embedded eutectic PCM may be a potentially well-suited material for medium- and low-temperature applications.