Multifunctional MIL-101(Cr)-NH2/expanded graphite/multi-walled carbon nanotube/paraffin wax composite phase change materials with excellent thermal conductivity and highly efficient thermal management for electronic devices

Abstract

Improving the thermal conductivity and anti-leakage behavior of phase change materials (PCMs) is beneficial for their applications in thermal storage and thermal management. In this study, a series of shape-stable composite PCMs (CPCMs) were prepared using a simple physical blending and vacuum impregnation method. Metal–organic frameworks (MOFs) synthesized by a hydrothermal method can effectively avoid the leakage of paraffin wax (PW), while the synergistic effect of expanded graphite (EG) and multi-walled carbon nanotubes (MWCNTs) strengthened the internal heat transfer of the CPCMs. The thermal conductivity of the CPCM (S5) containing 4 wt% EG and 1 wt% MWCNTs is 10.6 times higher than that of PW (2.23 vs. 0.21 W m⁻¹ k⁻¹). The sample S5 exhibits excellent latent heat (80.8 J g⁻¹), resistance (3846 Ω), thermal cycling stability, and shape stability and superior thermal management performance. The feasible preparation strategy for PCMs provided here has enormous potential applications in electronic product thermal management and thermal energy harvesting.