Abstract：
Cellulose papers (CPs) possess a pore structure, rendering them ideal precursors for carbon scaffolds because of their renewability. However, achieving a tradeoff between high electromagnetic shielding effectiveness and low reflection coefficient poses a tremendous challenge for CP-based carbon scaffolds. To meet the challenge, leveraging the synergistic effect of gravity and evaporation dynamics, laminar CP-based carbon scaffolds with a bidirectional gradient distribution of Fe3O4 nanoparticles were fabricated via immersion, drying, and carbonization processes. The resulting carbon scaffold, owing to the bidirectional gradient structure of magnetic nanoparticles and unique laminar arrangement, exhibited excellent in-plane electrical conductivity (96.3 S/m), superior electromagnetic shielding efficiency (1805.9 dB/cm2 g), low reflection coefficients (0.23), and a high green index (gs, 3.38), suggesting its green shielding capabilities. Furthermore, the laminar structure conferred upon the resultant carbon scaffold a surprisingly anisotropic thermal conductivity, with an in-plane thermal conductivity of 1.73 W/m K compared to a through-plane value of only 0.07 W/m K, confirming the integration of thermal insulation and thermal management functionalities. These green electromagnetic interference shielding materials, coupled with thermal insulation and thermal management properties, hold promising prospects for applications in sensitive devices.
摘要：
纤维素纸（CP）具有孔结构，由于它们的可再生性，它们成为碳支架的理想前体。然而,实现高电磁屏蔽效能和低反射系数之间的权衡对CP基碳支架提出了巨大的挑战。为了迎接挑战，利用重力和蒸发动力学的协同效应，层状CP基碳支架具有双向梯度分布的Fe3O4纳米粒子通过浸渍制备，干燥,和碳化过程。由此产生的碳支架，由于磁性纳米粒子的双向梯度结构和独特的层状排列，表现出优异的面内电导率（96.3S/m），卓越的电磁屏蔽效率（1805.9dB/cm2g），低反射系数(0.23)，和高绿色指数(gs，3.38),暗示了它的绿色屏蔽能力。此外，层状结构赋予了所得的碳支架令人惊讶的各向异性热导率，面内热导率为1.73W/mK，而通过面内热导率仅为0.07W/mK，确认隔热和热管理功能的集成。这些绿色的电磁干扰屏蔽材料，加上隔热和热管理性能，在敏感器件中的应用前景看好。
