The MDPI company has published the results of a new study, according to which old paper newspapers are recognized as the most promising raw materials for growing carbon nanotubes. The demand for them is only growing, and scientists have already developed technologies for the formation of nanotubes on the remains of organic substances, on animal or industrial waste, on synthetic materials. But the old newspapers had two undeniable advantages.
Newspapers, which are sets of paper sheets, were named by the study authors as an ideal 2D platform for growing nanotubes. Firstly, they are extremely cheap, including the cost of surface preparation procedures before the start of the process. Secondly, the process can be easily scaled by simply adding new newspaper sheets to the installation - each of them is a kind of section in the general "farm".
But there is also a fundamental limitation - only newspapers on paper filled with kaolin, aka porcelain clay, are suitable for growing carbon nanotubes. Not talc or titanium dioxide, which is added to paper for durability, and not even calcium carbonate, namely kaolin. It has been experimentally proven that when using iron as a catalyst, kaolin provides the best chemical conditions for tube growth.
As noted by Andrew Barron, a professor at Rice University in the United States, the study summarizes the best opportunities to reduce the cost of both the substrate and the post-synthesis process. And this, in turn, provides a transition to the mass, streaming production of single-walled carbon nanotubes.