Engineering multifunctional phase change composites enabled by dual-interpenetrating hybrid scaffold for excellent thermal conductivity and electromagnetic absorption

[Display omitted] •A multifunctional PCC is developed based on a dual-interpenetrating design of integrating MXene-Co aerogel in graphene array.•3D GMC provides orientational-interlinked highways for heat transfer, multi-heterointerface electric/magnetic hybrid architecture for microwave absorption, and stronger capillary action for encapsulating PW.•GMC/PW isochronally displays high κ, absorption-dominated EMI SE, admirable enthalpy density, and leakage-free performance.•GMC/PW manifests comprehensive applicability in electronic thermal management, anti-EM radiation, and solar energy utilization. Multi-function phase change composites (PCCs) with integrated high thermal conductivity (κ) and electromagnetic interference shielding efficiency (EMI SE) are crucially desired for advanced thermo-related devices. Herein, we report a dual ice-templating assembly strategy to develop a dual-interpenetrated hybrid scaffold for encapsulating paraffin wax (PW). The hybrid scaffold is coupled by hierarchical high-quality graphene array (HGA) and porous MXene-Co aerogel, and designated as GMC. The GMC can provide consecutive/oriented freeways with ultralow thermal resistance for efficient heat transfer, and multi-heterointerface electric/magnetic hybrid architecture for absorption-dominated EMI SE. Impressively, the tailored GMC/PW achieves a high κ of 7.82 W m−1 K−1, attractive EMI SE of 72.86 dB (absorption coefficient: 0.704), and admirable enthalpy density of 231.5 J g−1, together with leakage-free behavior and salient charging/discharging durability. Furtherly, the free-standing GMC/PW-supported devices are developed for thermal energy harvesting, management and utilization. This work offers an innovative approach for exploiting advanced PCCs, and expands their applicability in electronic thermal management, anti-EM radiation, and solar energy utilization.