Multifunctional paraffin wax/carbon nanotube sponge composites with simultaneous high-efficient thermal management and electromagnetic interference shielding efficiencies for electronic devices

As the operating speed and efficiency of electronic devices increase continuously, developing their thermal management and electromagnetic shielding capabilities has become extremely important. In this study, we prepared a paraffin wax/carbon nanotube sponge (PW@CNS) composite with simultaneous high-efficient thermal management and electromagnetic interference shielding functions via the simple vacuum impregnation method. The PW component functions as the phase change working substance for thermal management applications, and whereas the three-dimensional electrically conductive CNS component forms the matrix supporting the PW and a shielding structure against electromagnetic waves. The properties of PW@CNS are characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Its latent heat and relative enthalpy efficiency during melting and freezing process are as high as 248.8 J/g and 247.7 J/g, and 96.2% and 96.3%, respectively. After 100 thermal cycles, the latent heat remained nearly constant, and the prepared PW@CNS exhibited the excellent thermal management behavior and electromagnetic interference (EMI) shielding effectiveness (SE). All the results indicate that this PW@CNS has great potential as a thermal management and electromagnetic interference shielding material for electronic devices.