Polymer nanocomposites with excellent electromagnetic interference (EMI) shielding and thermal conductivity (TC) are urgently needed to solve the increasingly serious electromagnetic pollution and heat accumulation in devices. Herein, a distinct strategy was proposed to improve the dispersity of graphene nanoplatelets (GNPs) and integrate cellulose nanofiber (CNF), graphene nanoplatelets (GNPs), and MXene into a layered structure. The presence of MXene can improve the dispersity of GNPs, and the presence of GNPs can protect MXene from oxidation. By combining the excellent electrical conductivity of MXene and the high thermal conductivity of GNPs, the CNF/GNPs/MXene composite films exhibit excellent EMI shielding performance and high in-plane thermal conductivity. The electromagnetic shielding property of the CNF/GNPs/MXene composite films reaches 33.74 dB and the in-plane TC is 8.55 W/(m·K) when the total filler content is 50 wt % while the thickness of the composite film is only 38.5 μm. In addition, the mechanical properties of the composite membrane can meet general requirements. Therefore, these ultrathin CNF/GNPs/MXene composite films show great application potential as effective EMI shielding and thermal management materials.

Constructing superhydrophobic surfaces by simple and low-cost methods remains a challenge in achieving the large-scale commercial application of superhydrophobic materials. Herein, a facile two-step process is presented to produce a self-healing superhydrophobic surface on wood to improve water and mildew resistance. In this process, the natural hierarchical structure of wood is firstly modified by sanding with sandpaper to obtain an appropriate micro/nano composite structure on the surface, then a fluoroalkylsilane/silica composite suspension is cast and dried on the wood surface to produce the superhydrophobic surface. Due to the full use of the natural hierarchical structure of wood, the whole process does not need complicated equipment or complex procedures to construct the micro/nano composite structure. Moreover, only a very low content of inorganic matter is needed to achieve superhydrophobicity. Encouragingly, the as-obtained superhydrophobic surface exhibits good resistance to abrasion. The superhydrophobicity can still be maintained after 45 abrasion cycles under the pressure of 3.5 KPa and this surface can spontaneously recover its superhydrophobicity at room temperature by self-healing upon damage. Moreover, its self-healing ability can be restored by spraying or casting the fluoroalkylsilane/silica composite suspension onto this surface to replenish the depleted healing agents. When used for wood protection, this superhydrophobic surface greatly improves the water and mildew resistance of wood, thereby prolonging the service life of wood-based materials.

With the rapid development of electronic equipment and communication technology, it is urgent to develop composites with absorption-dominated and high electromagnetic interference shielding effectiveness (EMI SE) to prevent secondary...

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