US Patent 8124503 - CNT diameter selection by pretreatment of metal catalysts

http://www.freepatentsonline.com/8124503.html

This patent from William Marsh Rice University teaches a way to fabricate small diameter (<1nm) carbon nanotubes by modifying catalyst particles prior to CVD growth. Claim 1 reads:

1. A method for producing at least one nanotube, said method comprising the steps of:

placing at least one catalyst particle on a nanotube growth substrate surface;

modifying said at least one catalyst particle; and

growing said at least one nanotube, wherein said step of modifying said at least one catalyst particle comprises modifying the diameter of said at least one catalyst particle, by chemically treating, wherein the chemically treating comprises reducing with a liquid solution.