Revealing the mechanism of significant enhancement in interfacial thermal transport in silicon-based ceramic crystalline/amorphous matrix composite phase change materials

Investigating thermal transport mechanisms at the interface between phase change materials (PCMs) and high thermally conductive fillers has become increasingly significant in developing phase change energy storage technologies. This study explores the interfacial thermal transport between a representative PCM, erythritol, and various fillers, including crystalline (SiC, Si₃N₄) and amorphous (SiO₂) nanoparticles, using molecular dynamics (MD) simulations. Additionally, time-domain thermoreflectance (TDTR) experiments were performed to quantify the interfacial thermal conductance between erythritol and the three types of fillers, yielding values of 50.1, 40.0, and 25.6 MW m^–2 K⁻¹. These results align well with the trends observed in the simulations. Furthermore, the underlying mechanisms of interfacial heat transfer were analyzed by examining the phonon density of states, overlap energy, and interaction energy. This research provides innovative insights into nanoscale interfacial thermal transport in composite PCMs. This could lead to significant advancements in thermal management technologies, particularly in developing more efficient thermal energy storage systems.