Method for producing carbon material

Abstract

The present invention provides a method for manufacturing diamond, comprising electrolytically reducing carbon dioxide into diamond to obtain diamond in an electrolytic reduction apparatus having an anode, a cathode, and an electrolytic solution containing carbon dioxide, wherein the electrolytic solution comprises an ionic liquid.

1 .- 18 . (canceled) 
     
     
         19 . A method for manufacturing a carbon material, comprising electrolytically reducing carbon dioxide into diamond to obtain diamond in an electrolytic reduction apparatus having an anode, a cathode, and an electrolytic solution containing carbon dioxide,
 wherein the electrolytic solution comprises an ionic liquid,   the ionic liquid is an imidazolium-based ionic liquid, an aromatic ionic liquid, a pyrrolidinium-based ionic liquid, an ammonium-based ionic liquid, a piperidinium-based ionic liquid, or a quaternary phosphonium-based ionic liquid, and   a temperature of the electrolytic solution is 0 to 100° C.   
     
     
         20 . The method for manufacturing a carbon material according to  claim 19 , wherein:
 the anode is a Pt electrode, and   the cathode is an Ag electrode.   
     
     
         21 . The method for manufacturing a carbon material according to  claim 19 , wherein the ionic liquid is N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium tetrafluoroborate, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide, N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium tetrafluoroborate, triethylpentylphosphonium bis(trifluoromethanesulfonyl)imide, triethyloctylphosphonium bis(trifluoromethanesulfonyl)imide, or tributylmethylphosphonium bis(trifluoromethanesulfonyl)imide. 
     
     
         22 . The method for manufacturing a carbon material according to  claim 19 , wherein the electrolytic solution comprises a supporting electrolyte. 
     
     
         23 . The electrolytic reduction method according to  claim 19 , wherein the supporting electrolyte is KHCO 3 , KHPO 4 , LiBF 4 , LiPF 6 , LiClO 4 , LiAsF 6 , LiTf, LiTFSI, LiFSI, K 2 CO 3 , Li 2 CO 3 , Na 2 CO 3 , or NaHCO 3 . 
     
     
         24 . The electrolytic reduction method according to  claim 19 , wherein the supporting electrolyte is LiBF 4 , LiPF 6 , LiTFSI, or LiFSI. 
     
     
         25 . The electrolytic reduction method according to  claim 19 , wherein a concentration of the supporting electrolyte contained in the ionic liquid is from 0.01 mol/L to a saturated concentration. 
     
     
         26 . The electrolytic reduction method according to  claim 19 , wherein the electrolytic reduction apparatus further comprises a reference electrode, the reference electrode is a Ag + /Ag electrode, and a potential of the cathode is −5.0 V to −0.5 V. 
     
     
         27 . The electrolytic reduction method according to  claim 19 , wherein the electrolytic reduction is performed at ordinary temperature and normal pressure. 
     
     
         28 . The electrolytic reduction method according to  claim 19 , the carbon material is diamond, graphite, glassy carbon, amorphous carbon, carbon nanotube, carbon nanohorn, or graphene. 
     
     
         29 . The electrolytic reduction method according to  claim 19 , the carbon material is diamond. 
     
     
         30 . An electrolytic reduction apparatus having an anode, a cathode, and an electrolytic solution containing carbon dioxide, wherein:
 the electrolytic solution comprises an ionic liquid selected from an imidazolium-based ionic liquid, an aromatic ionic liquid, a pyrrolidinium-based ionic liquid, an ammonium-based ionic liquid, a piperidinium-based ionic liquid, and a quaternary phosphonium-based ionic liquid,   carbon dioxide in the electrolytic solution is reduced into diamond, and   the anode is a Pt electrode, and the cathode is a Ag electrode.   
     
     
         31 . The electrolytic reduction apparatus according to  claim 30 , wherein the ionic liquid is N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium tetrafluoroborate, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide, N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium tetrafluoroborate, triethylpentylphosphonium bis(trifluoromethanesulfonyl)imide, triethyloctylphosphonium bis(trifluoromethanesulfonyl)imide, or tributylmethylphosphonium bis(trifluoromethanesulfonyl)imide. 
     
     
         32 . The electrolytic reduction apparatus according to  claim 30 , wherein the electrolytic solution comprises a supporting electrolyte. 
     
     
         33 . The electrolytic reduction apparatus according to  claim 32 , wherein the supporting electrolyte is KHCO 3 , KHPO 4 , LiBF 4 , LiPF 6 , LiClO 4 , LiAsF 6 , LiTf, LiTFSI, LiFSI, K 2 CO 3 , Li 2 CO 3 , Na 2 CO 3 , or NaHCO 3 . 
     
     
         34 . The electrolytic reduction apparatus according to  claim 32 , wherein the supporting electrolyte is LiBF 4 , LiPF 6 , LiTFSI, or LiFSI. 
     
     
         35 . The electrolytic reduction apparatus according to  claim 32 , wherein a concentration of the supporting electrolyte contained in the ionic liquid is from 0.01 mol/L to a saturated concentration. 
     
     
         36 . The electrolytic reduction apparatus according to  claim 30 , the carbon material is diamond, graphite, glassy carbon, amorphous carbon, carbon nanotube, carbon nanohorn, or graphene. 
     
     
         37 . The electrolytic reduction apparatus according to  claim 30 , the carbon material is diamond.