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Here, we demonstrate a breathing-like passive thermal management material based on moisture adsorption and desorption of graphene oxide (GO) modified chromium (III) terephthalate metal organic framework (MIL-101Cr), which breaks the limitation of latent heat limitation of common phase change materials and is highly desirable for long-term heat dissipation of batteries and chips. Nanoscale MIL-101Cr (50∼100 nm) in-situ grown on the surface of GO (MIL-101Cr@GO) were prepared using a simple hydrothermal reaction method. In which, the MIL-101Cr acts as moisture adsorbent thus enables us to realize efficient heat dissipation through its moisture adsorption and desorption; while the GO acts as the nucleating agent for the growth of MIL-101Cr thus increases the nucleation rate and reduces the grain size of MIL-101Cr. As a result, the MIL-101Cr@GO shows high specific surface area and pore volume than that of pristine MIL-101Cr, resulting in higher moisture adsorption capacity and adsorption rate. In particular, the thermal management material MG6 (composed of MIL-101Cr and 6 wt% GO) shows a high moisture adsorption capacity of 1.391 g·g-1 (i.e., 1 g absorbent can absorb 1.391 g moisture), 35.44% higher than that of MIL-101Cr. The thermal management material MG6 achieves 9.0 °C temperature drop under 95% relative humidity for a ceramic heater with a heating power of 4W (similar to a typical Li-ion battery), and keep at ∼43.2 °C for at least 2 hours. In addition, the material MG6 can remain 95% moisture adsorption capacity after 144 hours of continuous operation, showing good thermal management performance and stability.

Electronic packaging materials with efficient heat dissipation and anti-electromagnetic-interference performance are highly desirable to realize the long-term stable operation of highly integrated electronic devices. Such combined functions of heat dissipation and anti-electromagnetic-interference are achieved here by filling 3D CNF@C-Ni network skeleton in epoxy resins (EP). The CNF@C-Ni is a carbon nanofibers network skeleton embedded with micron flower-like C-Ni particles and has been obtained by carbonizing nickel metal–organic frameworks (Ni-MOF) embellished bacterial cellulose. The 3D CNF@C-Ni network skeleton provides a highly efficient heat transfer channel for EP, rendering a high thermal conductivity of 0.5 W·m−1K−1 at room temperature for the 5 wt% CNF@C-Ni filled EP, ~2.8 times higher than that of pristine EP. In addition, the flower-like C-Ni particles realize an optimization in the impedance matching of CNF@C-Ni/EP, enabling a high electromagnetic wave absorption performance in the wave-transparent epoxy resins. In particular, a lowest reflection loss value of −49.77 dB at 13.44 GHz with a maximum effective bandwidth of 5.44 GHz (from 12.08 to 17.52 GHz) has been achieved in the 5 wt% CNF@C-Ni filled epoxy resins with a thickness of 2.2 mm. Such a new dual-functionated epoxy resin with combined high electromagnetic wave absorption and thermal management performance shows great potential in manufacturing of highly integrated electronic devices.