Phase change composite based on lignin carbon aerogel/nickel foam dual-network for multisource energy harvesting and superb EMI shielding

With the increasingly rapid pace of updates and iterations in electronic devices, electronic equipment/systems are becoming progressively intricate, aiming to achieve swift responsiveness through higher packaging density, which leads to electromagnetic interference and brings along with it heat accumulation, the creation of new composite phase change materials with efficient thermal management capabilities integrated with excellent electromagnetic interference shielding capabilities is imminent. In this study, nickel foam/lignin/rGO dual network scaffolds (LGN) with high electrical conductivity were prepared by vacuum-assisted adsorption, freeze-drying, and thermal annealing, and then PEG was encapsulated in LGN by vacuum impregnation to obtain shape-stabilized PEG/NiF/LN-rGO (PLGN) composite phase change material. The results demonstrate that the prepared PLGNs exhibit robust stability, exceptional thermal management capabilities, and commendable electromagnetic interference (EMI) shielding effectiveness (SE). Among these composites, PLGN-3 stands out with a notably high energy storage density, featuring a melting enthalpy of 140.95 J/g and a relative enthalpy efficiency of 98.72 %. Benefiting from its outstanding electrical conductivity (1597.5 S/cm for PLGN-3) and superior light absorption, the PLGN composite phase change material also demonstrates highly effective photothermal and electrothermal conversion capabilities. In addition, the EMI shielding effectiveness reaches up to 69.9 dB at 8.2-12.4 GHz. In conclusion, the synthesized PLGN composite phase change material demonstrates considerable promise for mitigating electromagnetic interference and facilitating thermal energy management in electronic devices.