Porous metal oxide and method of preparing the same

Abstract

Porous metal oxides are provided. The porous metal oxides are prepared by heat treating a coordination polymer. A method of preparing the porous metal oxide is also provided. According to the method, the shape of the particles of the metal oxide can be easily controlled, and the shape and distribution of pores of the porous metal oxide can be adjusted.

1 . A method of preparing a porous metal oxide, comprising heat treating a coordination polymer. 
   
   
       2 . The method of  claim 1 , wherein the heat treating comprises:
 a first heat treatment process conducted under an inert atmosphere; and   a second heat treatment process conducted under an oxygen-containing atmosphere.   
   
   
       3 . The method of  claim 2 , wherein the first heat treatment process is conducted at a temperature ranging from about 300° C. to about a melting point of a metal included in the coordination polymer. 
   
   
       4 . The method of  claim 1 , wherein the second heat treatment process is conducted at a temperature ranging from about 300 to about 1500° C. 
   
   
       5 . The method of  claim 1 , wherein the coordination polymer comprises a compound having a unit structure represented by Formula 1:
   M x L y S z   Formula 1   wherein M is a metal selected from the group consisting of transition metals, Group 13 metals, Group 14 metals, Group 15 metals, lanthanides, actinides and combinations thereof, L is a multi-dentate ligand capable of forming ionic or covalent bonds with at least two metal ions, S is a mono-dentate ligand capable of forming an ionic or covalent bond with one metal ion, wherein d represents a number of functional groups of L capable of binding to a metal ion, and wherein x, y and z are integers satisfying Equation 1:
     yd+z≦ 6 x.   Equation 1 
   
   
   
       6 . The method of  claim 5 , wherein the coordination polymer forms a network by connecting metal ions with the multi-dentate ligand. 
   
   
       7 . The method of  claim 5 , wherein the multi-dentate ligand is selected from the group consisting of trimesate-based ligands represented by Formula 4, terephthalate-based ligands represented by Formula 5, 4,4′-bipyridine-based ligands represented by Formula 6, 2,6-naphthalenedicarboxylate-based ligands represented by Formula 7, pyrazine-based ligands represented by Formula 8 and combinations thereof: 
     
       
         
         
             
             
         
       
       wherein R 1  to R 25  are each independently selected from the group consisting of hydrogen atoms, halogen atoms, hydroxy groups, substituted C 1-20  alkyl groups, unsubstituted C 1-20  alkyl groups, substituted C 1-20  alkoxy groups, unsubstituted C 1-20  alkoxy groups, substituted C 2-20  alkenyl groups, unsubstituted C 2-20  alkenyl groups, substituted C 6-30  aryl groups, unsubstituted C 6-30  aryl groups, substituted C 6-30  aryloxy groups, unsubstituted C 6-30  aryloxy groups, substituted C 2-30  heteroaryl groups, unsubstituted C 2-30  heteroaryl groups, substituted C 2-30  heteroaryloxy groups, unsubstituted C 2-30  heteroaryloxy groups and combinations thereof. 
     
   
   
       8 . The method of  claim 5 , wherein the metal is selected from the group consisting of Fe, Pt, Co, Cd, Cu, Ti, V, Cr, Mn, Ni, Ag, Pd, Ru, Mo, Zr, Nb, La, In, Sn, Pb, Bi and combinations thereof. 
   
   
       9 . A porous metal oxide prepared according the method of  claim 1 . 
   
   
       10 . A porous metal oxide prepared according to the method of  claim 5 . 
   
   
       11 . A porous metal oxide comprising a plurality of pores having an average diameter of about 10 nm or greater, wherein the porous metal oxide has a multilateral shape. 
   
   
       12 . The porous metal oxide of  claim 11 , wherein the average diameter of the pores ranges from about 20 to about 100 nm. 
   
   
       13 . The porous metal oxide of  claim 11 , wherein particles of the porous metal oxide have a shape selected from the group consisting of needles and plates. 
   
   
       14 . The porous metal oxide of  claim 11 , wherein the porous metal oxide is obtained by heat-treating a coordination polymer. 
   
   
       15 . The porous metal oxide of  claim 14 , wherein the coordination polymer comprises a compound having a unit structure represented by Formula 1:
   M x L y S z   Formula 1.   wherein M is a metal selected from the group consisting of transition metals, Group 13 metals, Group 14 metals, Group 15 metals, lanthanides, actinides and combinations thereof, L is a multi-dentate ligand capable of forming ionic or covalent bonds with at least two metal ions, S is a mono-dentate ligand capable of forming an ionic or covalent bond with one metal ion, wherein d represents a number of functional groups of L capable of binding to a metal ion, and wherein x, y and z are integers satisfying Equation 1:
     yd+z≦ 6 x.   Equation 1 
   
   
   
       16 . The porous metal oxide of  claim 15 , wherein the coordination polymer forms a network by connecting metal ions with the multi-dentate ligand. 
   
   
       17 . The porous metal oxide of  claim 15 , wherein the multi-dentate ligand is selected from the group consisting of trimesate-based ligands represented by Formula 4, terephthalate-based ligands represented by Formula 5, 4,4′-bipyridine-based ligands represented by Formula 6, 2,6-naphthalenedicarboxylate-based ligands represented by Formula 7, pyrazine-based ligands represented by Formula 8 and combinations thereof: 
     
       
         
         
             
             
         
       
       wherein R 1  to R 25  are each independently selected from the group consisting of hydrogen atoms, halogen atoms, hydroxy groups, substituted C 1-20  alkyl groups, unsubstituted C 1-20  alkyl groups, substituted C 1-20  alkoxy groups, unsubstituted C 1-20  alkoxy groups, substituted C 2-20  alkenyl groups, unsubstituted C 2-20  alkenyl groups, substituted C 6-30  aryl groups, unsubstituted C 6-30  aryl groups, substituted C 6-30  aryloxy groups, unsubstituted C 6-30  aryloxy groups, substituted C 2-30  heteroaryl groups, unsubstituted C 2-30  heteroaryl groups, substituted C 2-30  heteroaryloxy groups, unsubstituted C 2-30  heteroaryloxy groups and combinations thereof. 
     
   
   
       18 . The porous metal oxide of  claim 15 , wherein the metal is metal selected from the group consisting of Fe, Pt, Co, Cd, Cu, Ti, V, Cr, Mn, Ni, Ag, Pd, Ru, Mo, Zr, Nb, La, In, Sn, Pb, Bi and combinations thereof. 
   
   
       19 . An active material for a secondary battery comprising the porous metal oxide of  claim 11 . 
   
   
       20 . An active material for a secondary battery comprising the porous metal oxide of  claim 15 . 
   
   
       21 . A catalyst comprising the porous metal oxide of  claim 11 . 
   
   
       22 . A catalyst comprising the porous metal oxide of  claim 15 . 
   
   
       23 . A support for a catalyst comprising the porous metal oxide of  claim 11 . 
   
   
       24 . A support for a catalyst comprising the porous metal oxide of  claim 15 .