Korea Research Institute of Chemical Technology

Ha-Kyun Jung

Chang-Gyoun Kim

Hee Dong Park

Young-Min Choi

Ki-Jeong Kong

Bu Young Sung

Hyun-Ju Chang

Jae-do Lee

Beyong-Hwan Ryu

Han-Sung Park

This invention relates to a method to induce growth of carbon nanotubes using a liquid phased-hydrocarbon based material under a critical range of equilibrating between liquid and gas phases, thereby easily manipulating a required carbon source. This invention also relates to a method to facilitate easy generation of a carbon backbone of the carbon nanotube because the reaction is performed in the presence of a metal nanoparticle or a metal compound capable of spontaneously generating a seed catalyst which stimulates the growth of carbon nanotubes as well as secures safety enough for the industrial application by using a mild reaction condition within the critical range. Accordingly, this invention can produce the carbon nanotube with high transition efficiency under a mild condition with a relatively lower temperature and pressure than those in conventional gas phased-methods without using a costly equipment, thereby cost-effectively producing the carbon nanotube in large quantities.

Method of preparing carbon nanotube from liquid phased-carbon source

This invention relates to a process for preparing a spherical green-emitting phosphor based on zinc orthosilicate and more particularly, to the process for a zinc orthosilicate-based green-emitting phosphor demonstrating an emission spectrum at visible regions, when excited by electron beam, via a new application of 'the homogeneous precipitation method' comprising the following steps such as i) a solution of tetraethylorthosilicate (TEOS) diluted in ethanol is hydrolyzed to obtain a hydrated silica, ii) said hydrated silica is dispersed together with the solution containing zinc and manganese components, iii) a precipitant selected from oxalic acid and oxalates is added to said dispersed solution together with a basic solution, while precipitating zinc and manganese components, iv) said admixture precipitate, so filtered off and dried, is calcined in the air and reheated under the reducing atmosphere to generate a phosphor powder; hence, the above-described phosphor particle is quite effective in a variety of display fields of industry including PDP, since it has a spherical shape with less agglomeration and homogeneous distribution of manganese, an activator, thus proving superior to the conventional phosphor prepared by the solid state reaction method in terms of brightness.

Preparing green phosphor based on zinc orthosilicate

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Daejeon, South Korea

Ha-Kyun Jung