Magnetic field assisted synthesis of magnetic nanoparticles

Abstract

A process for the production of magnetic nanoparticles having uniform size and shape in which a magnetic metallic substance selected from magnetic transitional metals, their alloys, and intermetallic alloys with non-magnetic metals, is dissolved in a non-aqueous medium, reacted with a reducing agent, in solution and the reaction mixture is subjected to an external magnetic field.

1 . A process for producing magnetic nanoparticles of uniform shape and size comprising: 
 a. forming a solution in a non-aqueous medium of a magnetic substance selected from the group consisting of magnetic transition metals, their salts and alloys and intermetallic alloys of said magnetic transition metals with non-magnetic metals;    b. adding a reducing agent to the solution to form a reaction mixture, and c. applying an external gradient magnetic field to the reaction mixture.    
     
     
         2 . A processing according to  claim 1  in which the non-aqueous medium is a lower alcohol.  
     
     
         3 . A process according to  claim 2  in which the alcohol is ethanol.  
     
     
         4 . A process according to  claim 1  in which the reducing agent is a borohydride.  
     
     
         5 . A process according to  claim 3  in which the magnetic substance is cobalt.  
     
     
         6 . A process according to  claim 1  in which the magnetic substance is cobalt.  
     
     
         7 . A process according to  claim 1  in which the magnetic substance is a cobalt alloy with a non-magnetic metal.  
     
     
         8 . A process according to  claim 1  wherein the magnetic substance is an alloy of cobalt and another magnetic transition metal.  
     
     
         9 . A process for producing magnetic nanoparticles of uniform size and shape comprising: 
 a. dissolving a cobalt salt in ethanol;    b. dissolving a borohydride compound in ethanol;    c. adding the borohydride solution to the cobalt salt solution so as to cause a reduction reaction in the mixture;    d. applying an external magnetic field to the reaction mixture.