Smooth surface induced glossy appearance of freestanding multiwall carbon nanotube sheet

Carbon nanotube (CNT) structures reported in the literature often have a black color with low reflectance and matt surface appearance. Only a few papers reported the high reflectance and glossy appearance of the CNT surface on a substrate. To our knowledge, no one has reported the glossy appearance of freestanding CNT. Herein, we have successfully fabricated a freestanding multi-walled CNT sheet with a glossy or mirror-like surface appearance. Raman spectroscopy confirmed that both matt and glossy freestanding CNT sheets have the same chemical composition. We found that the glossy freestanding CNT sheet has a relatively flat surface morphology compared to matt freestanding CNT sheet, as seen in the atomic force microscopy results. We attributed the glossy appearance due to a relatively flat surface morphology of the freestanding CNT sheet.