Ag nanoparticles were in-situ grown on the surface of MXene nanosheets to prepare thermally conductive hetero-structured MXene@Ag fillers. With polyvinyl alcohol (PVA) as the polymer matrix, thermally conductive MXene@Ag/PVA composite films were fabricated by the processes of solution blending, pouring, and evaporative self-assembly. With the same mass fraction, MXene@Ag-III (MXene/Ag, 2:1, w/w) presents more significant improvement in thermal conductivity coefficient (λ) than MXene@Ag, single MXene, Ag, and simply blending MXene/Ag. MXene@Ag-III/PVA composite films show dual functions of excellent thermal conductivity and electromagnetic interference (EMI) shielding. When the mass fraction of MXene@Ag-III is 60 wt.%, the in-plane λ (λ_∥), through-plane λ (λ_⊥), and EMI shielding effectiveness (EMI SE) are 3.72 and 0.41 W/(m·K), and 32 dB, which are increased by 3.1, 1.3, and 105.7 times than those of pure PVA film (0.91 and 0.18 W/(m·K), and 0.3 dB), respectively. The 60 wt.% MXene@Ag-III/PVA composite film also has satisfying mechanical and thermal properties, with Young’s modulus, glass transition temperature, and heat resistance index of 3.8 GPa, 58.5 and 175.3 °C, respectively.

在 MXene 纳米片表面原位生长Ag 纳米粒子，制备导热异质结构 MXene@Ag 填料。以聚乙烯醇 (PVA) 为聚合物基体，通过溶液共混、浇注和蒸发自组装等工艺制备导热 MXene@Ag/PVA 复合薄膜。在相同的质量分数下，MXene@Ag-III (MXene/Ag, 2:1, w/w) 比 MXene@Ag、单一 MXene、Ag 以及简单混合 MXene/ Ag。MXene@Ag-III/PVA复合薄膜表现出优异的导热性和电磁干扰（EMI）屏蔽双重功能。当 MXene@Ag-III 的质量分数为 60 wt.% 时，平面内 λ (λ _∥ )，平面内 λ (λ _⊥)、EMI屏蔽效能(EMI SE)分别为3.72和0.41 W/(m·K)、32 dB，分别比纯PVA薄膜(0.91和0.18 W/( m·K)和0.3 dB)。60 wt.% MXene@Ag-III/PVA 复合薄膜还具有令人满意的机械和热性能，杨氏模量、玻璃化转变温度和耐热指数分别为 3.8 GPa、58.5 和 175.3 °C。