Silver nanowires and preparation method thereof

Abstract

Silver nanowire with a diameter smaller than 100 nm and an aspect ratio from 150 to 300 is disclosed. The preparation method of the silver nanowires is also disclosed.

1 . A method of preparing silver nanowires, the method comprising:
 sequentially adding a copper salt and a silver salt to a glycol at a temperature of 140° C. to 160° C. to form a reaction solution;   preparing PVP (polyvinylpyrrolidone) glycol solution;   performing a first addition step to add 3 vol % to 4.5 vol % of the PVP glycol solution dropwisely to the reaction solution while the reaction solution is maintained at a temperature of 140° C. to 160° C.;   performing a second addition step to add the rest of the PVP glycol solution to the reaction solution at one time while the reaction solution is maintained at a temperature of 140° C. to 160° C.;   cooling the reaction solution; and   purifying silver nanowires.   
     
     
         2 . The method of  claim 1 , wherein the copper salt is selected from the group of CuCl 2 , CuBr 2 , and a combination thereof. 
     
     
         3 . The method of  claim 1 , wherein the silver salt is AgNO 3 . 
     
     
         4 . The method of  claim 1 , wherein the first PVP addition step is performed at a constant dropping rate in 2 to 4 minutes. 
     
     
         5 . The method of  claim 1 , wherein the molar ratio of the PVP to the copper salt is 750 to 1500, and the molar ratio of the PVP to the silver salt is 2 to 5. 
     
     
         6 . The method of  claim 1 , wherein the temperature of the reaction solution is 148° C. to 155° C. 
     
     
         7 . The method of  claim 1 , wherein the purifying method is centrifugation. 
     
     
         8 . The method of  claim 1 , wherein the glycol can selected from the group of ethylene glycol, propylene ethylene glycol, butylene ethylene glycol and a combination thereof. 
     
     
         9 . A silver nanowire having a diameter smaller than 100 nm and an aspect ratio of 150 to 300.