Thermal Behavior of Gold Nanoparticle-Enhanced Paraffin Phase Change Materials: Insights from Molecular Dynamics Simulation

Abstract

Phase change materials (PCMs) exhibit exceptional performance in thermal energy storage, as they absorb and release Heat during phase changes. However, their application is always limited due to their low thermal conductivity. This study uses molecular dynamics simulation to assess the effects of gold nanoparticles (Au-NPs) on paraffin-based PCMs. The simulation results demonstrate that Au nanoparticles (Au-NPs) greatly enhance the thermal performance of the material. For example, the temperature stabilized at 844 K (from 806 K w/o Au-NPs), the thermal conductivity increased from 1.03 to 1.14 W/m·K, the heat flux improved from 7.56 to 8.03 W/m2 (to transfer heat faster), increases maximum velocity from 0.075 to 0.082 Å/ps (which suggests a faster molecular motion), and a slight reduction in density from 0.0149 to 0.0146 atom/Å3 (which is the result of molecular restructuring when integrating Au-NPs). Through these enhancements, the paper demonstrates the importance of Au-NPs in addressing the issue of low thermal conductivity in PCMs. The results add significant understanding for designing and optimizing nanoparticle-enhanced PCMs for renewable energy storage, electronics cooling, and sustainable thermal management systems. This understanding of molecular behavior opens possibilities for improving efficiency and reliability in thermal energy storage technology. © 2025 Elsevier B.V., All rights reserved.