New metal nanocatalysts useful e.g. to synthesis carbon nanotubes with bundle growth type or cotton growth type and double-walled carbon nanotubes, which are useful in electronic emission devices, elements of electronic devices and sensors

摘要

Metal nanocatalysts (I) are new. Metal nanocatalysts of formula ((Ni, Co, Fe) x(Mo, V) y(Al 2O 3, MgO, SiO 2) z) (I) are new. x : 1-10; y : 0-5; and z : 2-15. Independent claims are included for: (1) the preparation of (I); and (2) controlling the growth types of carbon nanotubes using (I) in a method for synthesizing carbon nanotubes, comprising producing (I) using an aqueous metal catalyst derivative (x) comprising cobalt, iron and/or nickel, in the presence of a carrier body precursor (z), where the mole fraction of (x) and (z) is regulated such that x:z is equal to 1-10:2-15, and producing carbon nanotubes by supplying carbon gas in the presence of (I).