Methods for production of silver nanostructures

Abstract

Methods for producing silver nanostructures with improved dimensional control, yield, purity, monodispersity, and scale of synthesis.

1 . A method of producing silver nanostructures, the method comprising: 
 heating ethylene glycol;    forming a mixture by mixing a halide with the heated ethylene glycol;    mixing a silver nitrate (AgNO 3 ) solution with the mixture;    mixing a polyvinyl pyrrolidone (PVP) solution with the mixture; and    isolating silver nanostructures from the mixture.    
     
     
         2 . The method of  claim 1 , wherein the halide is a chloride.  
     
     
         3 . The method of  claim 2 , wherein the chloride comprises HCl.  
     
     
         4 . The method of  claim 1 , wherein the chloride included in the mixture is in a concentration ranging from about 0.1 mM to about 0.4 mM.  
     
     
         5 . The method of  claim 1 , wherein the isolated silver nanostructures comprise single-crystal silver nanocubes.  
     
     
         6 . The method of  claim 1 , wherein the ethylene glycol is heated to a temperature ranging from about 130° C. to about 150° C.  
     
     
         7 . The method of  claim 1 , wherein the ethylene glycol is heated to a temperature up to about 140° C.  
     
     
         8 . The method of  claim 1 , wherein the mixture is maintained at a temperature ranging from about 130° C. to about 150° C.  
     
     
         9 . The method of  claim 1 , wherein the mixture is maintained at a temperature up to about 140° C.  
     
     
         10 . The method of  claim 1 , wherein the mixture comprises AgNO 3  in a range from about 20 mM to about 30 mM.  
     
     
         11 . The method of  claim 1 , wherein the mixture comprises PVP in a range from about 30 mM to about 40 mM (calculated in terms of the PVP repeating unit).  
     
     
         12 . A method of producing silver nanostructures, the method comprising: 
 heating ethylene glycol;    forming a mixture by mixing a chloride with the heated ethylene glycol;    adding a silver nitrate (AgNO 3 ) solution and a polyvinyl pyrrolidone (PVP) solution to the mixture, wherein the PVP comprises an iron salt; and    isolating silver nanostructures from the mixture.    
     
     
         13 . The method of  claim 12 , wherein the isolated silver nanostructures comprise silver nanowires.  
     
     
         14 . The method of  claim 12 , wherein the isolated silver nanostructures comprise single-crystal silver nanocubes.  
     
     
         15 . The method of  claim 12 , wherein the iron salt is a ferrous salt or a ferric salt.  
     
     
         16 . The method of  claim 12 , wherein the iron salt is iron (III) acetylacetonate (Fe(acac) 3 ).  
     
     
         17 . The method of  claim 12 , wherein the iron salt is iron (II) acetylacetonate (Fe(acac) 2 ).  
     
     
         18 . The method of  claim 12 , wherein the iron salt is iron (III) chloride (FeCl 3 ).  
     
     
         19 . The method of  claim 12 , wherein the chloride comprises sodium chloride (NaCl)  
     
     
         20 . The method of  claim 12 , wherein the chloride is included in the mixture in a concentration ranging from about 0.5 mM to about 0.25 mM.  
     
     
         21 . The method of  claim 12 , wherein the isolated silver nanostructures comprise single-crystal silver nanocubes or silver nanowires depending of the concentration of the iron salt.  
     
     
         22 . The method of  claim 12 , wherein the iron salt is included in the mixture in a concentration ranging from about 0.1 μM to about 25 μM.  
     
     
         23 . The method of  claim 12 , wherein the concentration of the iron salt in the mixture ranges from about 0.44 μM to about 25 μM and produces silver nanostructures comprising nanowires.  
     
     
         24 . The method of  claim 12 , wherein the concentration of the iron salt is less than or equal to about 0.44 μM and produces silver nanostructures comprising nanowires.  
     
     
         25 . The method of  claim 12 , wherein the ethylene glycol is heated to a temperature in the range from about 150° C. to about 170° C.  
     
     
         26 . The method of  claim 12 , wherein the ethylene glycol is heated to a temperature up to about 160° C.  
     
     
         27 . The method of  claim 12 , wherein the mixture is maintained at a temperature ranging from about 150° C. to about 170° C.  
     
     
         28 . The method of  claim 12 , wherein the mixture is maintained at a temperature up to about 160° C.  
     
     
         29 . A method of producing right bypyramid silver nanostructures, the method comprising: 
 heating ethylene glycol;    forming a mixture by mixing a bromide with the heated ethylene glycol;    adding a silver nitrate (AgNO 3 ) solution to the mixture;    adding a polyvinyl pyrrolidone (PVP) solution to the mixture; and    isolating right bypyramid silver nanostructures from the mixture.    
     
     
         30 . The method of  claim 25 , wherein the bromide comprises HBr.  
     
     
         31 . The method of  claim 25 , wherein the PVP solution comprises HBr.  
     
     
         32 . A right bypyramid synthesized according to the method of  claim 25 .  
     
     
         33 . A method of producing silver nanocubes, the method comprising: 
 heating ethylene glycol;    forming a mixture by mixing a sulfide with the heated ethylene glycol;    adding a silver nitrate (AgNO 3 ) solution to the mixture;    adding a polyvinyl pyrrolidone (PVP) solution to the mixture; and    isolating silver nanocubes from the mixture.    
     
     
         34 . The method of  claim 33 , wherein the sulfide comprises a sodium sulfide (Na 2 S) solution.  
     
     
         35 . The method of  claim 33 , wherein the sulfide comprises a sodium hydrogen sulfide solution (NaHS).  
     
     
         36 . The method of  claim 33 , wherein the sulfide is included in the mixture in a concentration ranging from about 25  82  M to about 35 μM.  
     
     
         37 . The method of  claim 33 , wherein the mixture is maintained at a temperature of about 135° C. to about 165° C.  
     
     
         38 . The method of  claim 33 , wherein the PVP solution and the AgNO 3  solution are added to the mixture such that the molar ratio between the PVP (in terms of the PVP repeating unit) and the AgNO 3  (PVP: AgNO 3 ) in the mixture ranges from about 0.75:1 to 2.7:1.  
     
     
         39 . The method of  claim 33 , wherein the PVP solution and the AgNO 3  solution both comprise ethylene glycol.  
     
     
         40 . At least one gold nanocage synthesized by using at least one silver nanocube, produced by the method of  claim 33 , as a sacrificial template.