Nanopore Confinement-driven Synchronous Enhancement of Thermal and Mechanical Properties of Phase Change Materials

Phase change materials (PCM) need highly thermally conductive inorganic porous skeletons to encapsulate and shape to reduce their leakage and enhance their thermal conduction. With the pore size shrinking to nanoscale, the crystallization, kinematic and thermal transport behaviors of PCM would be significantly changed. This work experimentally corroborates an intriguing nanopore confinement space effect that synchronously enhances the thermal conductivity and Young's modulus of representative PCM once encapsulated in nanoporous aluminum oxide using nanometer resolution thermal and mechanical mapping technique. Molecular dynamic simulation further reveals that the shortened hydrogen bond length due to the nanopore confinement facilitates the heat conduction of PCM, which refreshes the routine understanding that smaller space leads to reduction in thermal and mechanical properties.