Solid electrolyte-based photoelectrochemical cell for production of pure hydrogen peroxide solution, and method of fabricating same

Abstract

Proposed are a photoelectrochemical cell for producing hydrogen peroxide, a method of fabricating the same, and a method of producing hydrogen peroxide using the photoelectrochemical cell. The photoelectrochemical cell includes a photoanode including a photocatalyst, a cathode, and a solid polymer electrolyte layer disposed between the photoanode and the cathode and including a solid polymer electrolyte. The photoelectrochemical cell is for use in the production of hydrogen peroxide, and can produce hydrogen peroxide with electric energy generated from solar energy without requiring the supply of external electric energy.

What is claimed is: 
     
         1 . A photoelectrochemical cell for use in production of hydrogen peroxide, the photoelectrochemical cell comprising:
 a photoanode comprising a photocatalyst;   a cathode; and   a solid polymer electrolyte layer disposed between the photoanode and the cathode and comprising a solid polymer electrolyte.   
     
     
         2 . The photoelectrochemical cell of  claim 1 , wherein the photocatalyst comprises:
 a support comprising titanium dioxide (TiO 2 ); and   a ruthenium oxide loaded on the support.   
     
     
         3 . The photoelectrochemical cell of  claim 2 , wherein the photoanode comprises 0.5 to 1 part by weight of the ruthenium oxide, with respect to 100 parts by weight of the photocatalyst. 
     
     
         4 . The photoelectrochemical cell of  claim 2 , wherein the support has any one form selected from the group consisting of a nanorod form, a nanoneedle form, a sphere form, and a cube form. 
     
     
         5 . The photoelectrochemical cell of  claim 4 , wherein the support has a nanorod form, and
 the nanorod-form support has a length of 2 to 2.5 μm and a thickness of 40 to 50 nm.   
     
     
         6 . The photoelectrochemical cell of  claim 1 , wherein the cathode comprises a carbon material and a compound loaded on the carbon material and represented by Structural Formula 1 below, 
       
         
           
           
               
               
           
         
         wherein in Structural Formula 1, 
         R is a hydrogen atom, a carboxyl group, a sulfonic acid group, an amino group, or a hydroxyl group. 
       
     
     
         7 . The photoelectrochemical cell of  claim 6 , wherein the carbon material comprises at least one selected from the group consisting of natural graphite, artificial graphite, a single-walled carbon nanotube (SWCNT), a double-walled carbon nanotube (DWCNT), a multi-walled carbon nanotube (MWCNT), carbon nanofiber (CNF), graphene oxide (GO), and carbon black. 
     
     
         8 . The photoelectrochemical cell of  claim 6 , wherein the cathode comprises 1 to 10 parts by weight of the compound represented by Structural Formula 1, with respect to 100 parts by weight of the carbon material. 
     
     
         9 . The photoelectrochemical cell of  claim 1 , wherein the solid polymer electrolyte layer comprises:
 a proton exchange membrane positioned to face the photoanode and comprising a cation exchange resin;   an anion exchange membrane positioned to face the cathode and comprising an anion exchange resin; and   a polymer bead positioned between the proton exchange membrane and the anion exchange membrane and comprising the solid polymer electrolyte.   
     
     
         10 . The photoelectrochemical cell of  claim 9 , wherein the cation exchange resin comprises Nafion. 
     
     
         11 . The photoelectrochemical cell of  claim 9 , wherein the anion exchange resin comprises a gel polystyrene crosslinked with divinylbenzene, the gel polystyrene comprising quaternary ammonium as the functional group. 
     
     
         12 . A method of fabricating a photoelectrochemical cell, the method comprising the steps of:
 (a) fabricating a photoanode comprising a photocatalyst;   (b) fabricating a cathode; and   (c) forming a solid polymer electrolyte layer comprising a solid polymer electrolyte between the photoanode and the cathode.   
     
     
         13 . The method of  claim 12 , wherein step (a) comprises the steps of:
 (a-1) applying a solution comprising a ruthenium precursor to a support comprising titanium dioxide; and   (a-2) drying the support coated with the solution comprising the ruthenium precursor to fabricate the photoanode that comprises the support comprising titanium dioxide (TiO 2 ) and the photocatalyst comprising ruthenium oxide loaded on the support.   
     
     
         14 . The method of  claim 13 , wherein the ruthenium precursor comprises RuCl 3 . 
     
     
         15 . The method of  claim 12 , wherein step (b) comprises the steps of
 (b-1) mixing a precursor of a compound represented by Structural Formula 1 below with a carbon material to prepare a mixed solution, and   (b-2) drying the mixed solution to fabricate the cathode comprising the carbon material on which the compound represented by the Structural Formula 1 is loaded,   
       
         
           
           
               
               
           
         
         wherein in Structural Formula 1, 
         R is a hydrogen atom, a carboxyl group, a sulfonic acid group, an amino group, or a hydroxyl group. 
       
     
     
         16 . The method of  claim 12 , wherein step (c) comprises the steps of:
 (c-1) positioning a proton exchange membrane comprising a cation exchange resin so as to face the photoanode;   (c-2) positioning an anion exchange membrane comprising an anion exchange resin so as to face the cathode; and   (c-3) positioning a polymer bead comprising the solid polymer electrolyte between the proton exchange membrane and the anion exchange membrane.   
     
     
         17 . A method of producing hydrogen peroxide, the method comprising the steps of:
 (1) providing a photoelectrochemical cell comprising a photoanode, a cathode, and a solid polymer electrolyte layer positioned between the photoanode and the cathode;   (2) oxidizing water at the photoanode under light irradiation to generate electrons (e − ), oxygen (O 2 ), and hydrogen ions (H + ), and reacting the electrons (e − ) with oxygen (O 2 ), and water at the cathode to generate active oxygen species and hydroxide ions (OH − ); and   (3) reacting the hydrogen ions (H + ) with the active oxygen species in the solid polymer electrolyte layer to produce hydrogen peroxide (H 2 O 2 ).   
     
     
         18 . The method of  claim 17 , wherein the active oxygen species comprise a hydroperoxyl radical (HO 2 . − ) and a superoxide radical (O 2 . − ). 
     
     
         19 . The method of  claim 17 , wherein the method produces hydrogen peroxide with electric energy generated from solar energy without requiring supply of external electric energy. 
     
     
         20 . The method of  claim 17 , further comprising the step of, after step (3),
 (4) adding water to the solid polymer electrolyte layer to dissolve the hydrogen peroxide to prepare an aqueous hydrogen peroxide solution, and discharging the prepared aqueous hydrogen peroxide solution from the solid polymer electrolyte layer to outside to obtain the aqueous hydrogen peroxide solution.