Electromagnetic Wave Absorption of Carbon Nanocoils Grown on Different Substrate Study

The study focuses on the growth of carbon nanocoils on different substrates and the results of its electrical measurement. Refining the traditional growing method, it grows carbon nanocoils on the silicon chip. The study provides various substrates ranging from copper grid, stainless steel meshes, Al foil, Cu foil, cotton and papers. It coats catalyst which composed of Fe and Sn on those various substrates. Then, the researcher grows carbon nanocoils with single_zone temperature CVD. With the refined method, a great amount of carbon nanocoils grows on the low-cost substrates. Finally, in order to measuring electromagnetic wave absorption, the specimen is covered with laminating film. It aims at probing the influence of electromagnetic wave absorption on the same catalytic concentration with different substrates.
The measuring electromagnetic waves mainly range from 18 GHz to75 GHz. The study finds out that the shield of grown specimen has significantly improved to electromagnetic waves. In addition, in order to measure the electromagnetic wave absorption in low frequency (1~18 GHz) affected by carbon nanocoils, the study particularly use paper as substrate. The result shows the electromagnetic wave absorption of paper substrate reaches -30 dB (absorption rate 99.9 %). Furthermore, it can reach -49 dB (26 GHz) by tripling the layers of the specimen.