SmCo-BASED ALLOY NANOPARTICLES AND PROCESS FOR THEIR PRODUCTION

Abstract

SmCo-based alloy nanoparticles composed mainly of a SmCo-based alloy containing Sm and Co as constituent elements, wherein the content of metal elements other than Sm and Co is 0.05-20 wt % with respect to the SmCo-based alloy.

1 . SmCo-based alloy nanoparticles composed mainly of a SmCo-based alloy containing Sm and Co as constituent elements, wherein the content of metal elements other than Sm and Co is 0.05-20 wt % with respect to the SmCo-based alloy. 
     
     
         2 . SmCo-based alloy nanoparticles according to  claim 1 , wherein the content of the metal elements is 0.05-10 wt % with respect to the SmCo-based alloy. 
     
     
         3 . SmCo-based alloy nanoparticles according to  claim 1 , wherein the metal elements include at least one element selected from the group consisting of Au, Ag, Pt, Pd, Rh, Ru, Ir, Os, Cu, Ni, Cr, Al and Mn. 
     
     
         4 . SmCo-based alloy nanoparticles according to  claim 1 , wherein the particle sizes are 1-30 nm. 
     
     
         5 . SmCo-based alloy nanoparticles according to  claim 1 , which are obtained by liquid synthesis wherein a strong reducing agent is added to an organic solvent containing a samarium salt, a cobalt salt and metal element salts, to reduce the samarium salt, the cobalt salt and the metal element salts. 
     
     
         6 . SmCo-based alloy nanoparticles according to  claim 1 , having a core-shell structure comprising a core section and a shell section covering the core section, wherein the proportion of the metal elements with respect to the SmCo-based alloy in the core section is greater than the proportion in the shell section. 
     
     
         7 . A process for production of SmCo-based alloy nanoparticles composed mainly of a SmCo-based alloy containing Sm and Co as constituent elements, the process comprising:
 a mixing step in which a starting material containing a samarium salt, a cobalt salt and salts of metal elements other than Sm and Co, as well as a protective agent, is mixed with a reducing organic solvent; and   a reduction step in which a strong reducing agent is added to the mixture and heated to reduce the samarium salt, the cobalt salt and the salts of the metal elements.   
     
     
         8 . A process for production of SmCo-based alloy nanoparticles according to  claim 7 , further comprising a dehydration step in which the mixture obtained from the mixing step is stirred and heated for uniform dissolution and dehydration and then cooled, prior to the reduction step. 
     
     
         9 . A process for production of SmCo-based alloy nanoparticles according to  claim 7 , wherein the metal elements include at least one element selected from the group consisting of Au, Ag, Pt. Pd, Rh, Ru, Ir, Os, Cu, Ni, Cr, Al and Mn. 
     
     
         10 . A process for production of SmCo-based alloy nanoparticles according to  claim 7 , wherein the strong reducing agent contains at least one compound selected from the group consisting of LiAlH 4 , NaBH 1 , N 2 H 4 , B 2 H 6  and LiBH(C 2 H 5 ) 3 .