Boron-doped graphene sheet as sodium-ion battery anode

Abstract

A sodium-ion battery having a boron-doped graphene sheet as an anode active material is provided. The boron-doped graphene sheet is of formula B x C y , where x and y satisfy a relation of x+y=4, and x is a number larger than 0 and less than or equal to 1.

1 . A sodium-ion battery, comprising:
 an anode comprising a boron-doped graphene sheet;   a cathode; and   an electrolyte comprising a sodium salt.   
     
     
         2 . The sodium-ion battery of  claim 1 , wherein the cathode comprises sodium. 
     
     
         3 . The sodium-ion battery of  claim 1 , wherein
 the boron-doped graphene sheet is of formula B x C y ,   x and y satisfy a relation of x+y=4, and   x is a number larger than 0 and less than or equal to 1.   
     
     
         4 . The sodium-ion battery of  claim 1 , wherein sodium adsorption occurs on a single side or both sides of the boron-doped graphene sheet. 
     
     
         5 . The sodium-ion battery of  claim 1 , wherein the boron-doped graphene sheet is B 0.5 C 3.5 . 
     
     
         6 . The sodium-ion battery of  claim 5 , wherein a maximum concentration of sodium adsorbed on a single side of the boron-doped graphene sheet is Na 0.625 (B 0.5 C 3.5 ). 
     
     
         7 . The sodium-ion battery of  claim 5 , wherein a maximum concentration of sodium adsorbed on both sides of the boron-doped graphene sheet is Na 0.75 (B 0.5 C 3.5 ). 
     
     
         8 . The sodium-ion battery of  claim 1 , wherein the boron-doped graphene sheet is BC 3 . 
     
     
         9 . The sodium-ion battery of  claim 8 , wherein a maximum concentration of sodium adsorbed on a single side of the boron-doped graphene sheet is Na 1.125 (BC 3 ). 
     
     
         10 . The sodium-ion battery of  claim 8 , wherein a maximum concentration of sodium adsorbed on both sides of the boron-doped graphene sheet is Na 1.33 (BC 3 ). 
     
     
         11 . The sodium-ion battery of  claim 1 , wherein the boron-doped graphene sheet comprises pre-adsorbed sodium. 
     
     
         12 . The sodium-ion battery of  claim 11 , wherein the pre-adsorbed sodium is adsorbed on a single side or on both sides of the boron-doped graphene sheet. 
     
     
         13 . The sodium-ion battery of  claim 11 , wherein a concentration of the pre-adsorbed sodium is equal to or larger than a concentration of boron. 
     
     
         14 . The sodium-ion battery of  claim 11 , wherein
 the boron-doped graphene sheet is of formula B x C y ,   x and y satisfy a relation of x+y=4, and   x is a number larger than 0 and less than or equal to 1.   
     
     
         15 . The sodium-ion battery of  claim 11 , wherein the boron-doped graphene sheet is B 0.5 C 3.5 . 
     
     
         16 . The sodium-ion battery of  claim 15 , wherein a maximum concentration of sodium pre-adsorbed on a single side of the boron-doped graphene sheet is Na 0.625 (B 0.5 C 3.5 ). 
     
     
         17 . The sodium-ion battery of  claim 15 , wherein a maximum concentration of sodium pre-adsorbed on both sides of the boron-doped graphene sheet is Na 0.75 (B 0.5 C 3.5 ). 
     
     
         18 . The sodium-ion battery of  claim 11 , wherein the boron-doped graphene sheet is BC 3 . 
     
     
         19 . The sodium-ion battery of  claim 18 , wherein a maximum concentration of sodium pre-adsorbed on a single side of the boron-doped graphene sheet is Na 1.125 (BC 3 ). 
     
     
         20 . The sodium-ion battery of  claim 18 , wherein a maximum concentration of sodium pre-adsorbed on both sides of the boron-doped graphene sheet is Na 0.33 (BC 3 ).