Graphene-Reinforced Ceramic Composites and Uses Therefor

Abstract

The disclosure provides novel graphene-reinforced ceramic composites and methods for making such composite materials.

We claim: 
     
         1 . A method for making a ceramic composite material, comprising
 (a) combining graphene with a ceramic material; and   (b) densifying the combination to produce a graphene-reinforced ceramic material.   
     
     
         2 . The method of  claim 1 , wherein the graphene and the ceramic material are each mixed with cationic surfactant prior to the combining step. 
     
     
         3 . The method of  claim 1 , wherein the graphene is present in the combination at between 0.5% to 1.5% on a volume percentage basis. 
     
     
         4 . The method of  claim 2 , wherein the cationic surfactant comprises cetyltrimethylammonium bromide (CTAB). 
     
     
         5 . The method of  claim 4 , wherein approximately 1% wt:wt of CTAB is mixed with the graphene and with the ceramic material. 
     
     
         6 . The method of  claim 1 , wherein the method comprises:
 (a) providing
 (i) a solution of graphene mixed with a cationic surfactant, wherein the solution has a pH of approximately 4; and 
 (ii) a solution of ceramic material mixed with a cationic surfactant, wherein the solution has a pH of approximately 4; 
   (b) sonicating
 (i) the solution of graphene under conditions suitable to disperse the graphene in the solution to produce a dispersed graphene solution; and 
 (ii) the solution of ceramic material under conditions suitable to disperse the ceramic material in the solution to produce a dispersed ceramic material solution; 
   (c) combining the dispersed graphene solution and the dispersed ceramic material solution to produce a composite mixture;   (d) sonicating the composite mixture under conditions suitable to disperse the graphene and the ceramic material in the composite mixture;   (e) milling the composite mixture;   (f) evaporating water from the composite mixture to produce a composite slurry;   (g) heat treating the composite slurry under conditions suitable to remove the cationic surfactant to produce a composite powder; and   (h) densifying the composite powder to produce the graphene-reinforced ceramic material.   
     
     
         7 . The method of  claim 6 , wherein the densifying comprises exposing the composite powder to:
 (i) rapid heating of approximately 100° C./minute up to a maximum temperature of between about 1500° C. and about 1700° C. for between about 2 minutes to about 5 minutes;   (ii) pressure application of approximately 35 MPa; and   (iii) electric current with a maximum pulse current of 3000 A and a maximum pulse voltage of 10 Volts.   
     
     
         8 . The method of  claim 7 , wherein the densifying is carried out using spark plasma sintering.