| 초록 |
We studied the effects of size-controlled copper nanosheets (Cu NSs) on both the internal porous structures and the EMI shielding performance. As a two-dimensional (2D) conductive fillers, Cu NSs was carefully synthesized and controlled their size by adjusting the concentrations of various ingredients such as shape modifier, stabilizer and reductant. In order to identify the relationship between internal structure and EMI SE, the size-controlled Cu NSs with the average size of 3.8 µm, 8.9 µm, and 12.2 µm were prepared. We found that the resulting EMI shielding films had different surface coverages, film thicknesses, and EMI shielding effectiveness (SE) at a fixed loading weight of 0.6 mg/cm2. Especially, the larger Cu NSs clearly formed a more hierarchical porous internal structure than the smaller ones, implying that multi-layered porous structure of the larger Cu NSs provided a longer traveling path for incident electromagnetic waves and allowed better EMI shielding performances. |
