PMMA-assisted electrospinning uniformly incorporates magnetic particles into carbon nanomaterials for efficient microwave absorption†

The development of magnetic–electric synergistic microwave-absorbing materials represents a pivotal strategy for optimizing impedance matching, overcoming skin effects, and enhancing absorbing performance. Achieving a uniform distribution of magnetic particles within the dielectric material during preparation poses an immense challenge. This study employed PMMA-assisted electrospinning to achieve a homogeneous dispersion of magnetic particles on the surface of 1D or 2D carbon nanomaterials. The electrospinning process effectively blends the precursor of the magnetic material with the carbon nanomaterials while utilizing PMMA as a sacrificial template to anchor and evenly disperse the magnetic particles onto the carbon material's surface. As anticipated, this approach ensures uniform modification of magnetic particles within the carbon matrix, thereby achieving ideal interface uniformity. Comparative analysis reveals that optimized samples incorporating carbon nanotubes and graphene exhibit significantly reduced minimum reflection loss by 294% and 313%, respectively, compared to those without electrospinning treatment. Further examination of the composite microstructure and electromagnetic parameters underscores that excellent dispersion of magnetic particles is crucial in improving impedance matching. This article presents a controllable and easily scalable preparation method for constructing interface–uniform dielectric–magnetic composite structures with exceptional homogeneity.