Investigating Long‐Term Durability of Nanofillers (TiO₂) Embedded Organic Eutectic Phase Change Composites

Phase Change Materials (PCMs) are generally considered as a potential candidate for thermal energy storage (TES) as they possess excellent latent heat. TES system's thermal management potential is greatly hampered due to the degraded thermal conductivity of PCMs. The present study explores the long‐term durability (potential degradation) of eutectic phase change composite loaded with TiO 2 nanoparticles. The synthesized nano‐enhanced eutectic phase change composite (NePCC) logged a maximal thermal conductivity of 0.6 W/mK with 0.5% nanofillers. Accelerated thermal cycling was performed on the NePCC with 0.5% TiO 2 nanoparticles (M2). The long‐term reliability of the NePCC (M2) was confirmed through a comprehensive morphological and thermophysical analysis after 4000 melt‐freeze cycles. The nano‐enhanced eutectic phase change material showed excellent thermal stability up to 100 °C even after 4000 thermal cycles, indicating its long‐term application prospects. Fourier Transform Infrared (FTIR) results of the thermally cycled sample (M2) proved the chemical stability of the NePCC. A negligible variation was found in latent heat and phase transition temperature values (for M2) after 4000 thermal cycles. Thermophysical characterization of the thermal cycled NePCC (M2) proves the thermal stability of the synthesized NePCC (M2), which is adequate for its usage in medium‐temperature TES systems.