Electrochemical cells and electrochemical methods

Abstract

An electrochemical cell and method for reducing carbon dioxide and/or dehydrogenating a hydrocarbon to an olefin are provided. The electrochemical cell includes a cathode having a first conducting component that is active toward adsorption and reduction of an oxidizing agent such as CO 2 ; and an anode having a second conducting component that is active toward adsorption and oxidation of a reducing agent such as a hydrocarbon. Additionally, a hydrophobic modifier is present on at least a portion of a surface of the second conducting component or both the first and second conducting components. The method includes exposing the cathode to a CO 2 -containing fluid; exposing the anode to a hydrocarbon-containing fluid; and applying a voltage between the cathode exposed to the CO 2 -containing fluid and the anode exposed to the hydrocarbon-containing fluid, wherein the voltage is sufficient to simultaneously oxidize the hydrocarbon via a dehydrogenation reaction and reduce the CO 2 .

What is claimed is: 
     
         1 . An electrochemical cell for reducing carbon dioxide, comprising:
 a cathode compartment including a cathode comprising a first conducting component that is active toward adsorption and reduction of CO 2 ;   an anode compartment including an anode comprising a second conducting component that is active toward adsorption and oxidation of a hydrocarbon, wherein the second conducting component is layered on an anode substrate surface, an overlying layer of the second conducting component incompletely covering an underlying layer of the second conducting component, and a hydrophobic modifier comprising an electrochemically reduced graphene oxide coating is present on both the first conducting component and the second conducting component;   a separator comprising an ion exchange membrane that physically separates the anode and cathode compartments and permits the passage of ions therebetween; and   wherein a hydrophobic modifier is present on at least a portion of a surface of the second conducting component, or both the first and second conducting components.   
     
     
         2 . The electrochemical cell of  claim 1 , wherein the second conducting component comprises a material selected from the group consisting of platinum (Pt), iridium (Ir), ruthenium (Ru), palladium (Pd), rhodium (Rh), nickel (Ni), cobalt (Co), iron (Fe), copper (Cu), and their combinations. 
     
     
         3 . The electrochemical cell of  claim 1 , wherein the second conducting component comprises platinum. 
     
     
         4 . The electrochemical cell of  claim 1 , wherein the hydrocarbon is selected from gaseous methane, ethane, propane, butane, pentane, and hexane. 
     
     
         5 . The electrochemical cell of  claim 1 , wherein the first conducting component is coupled to a substrate. 
     
     
         6 . The electrochemical cell of  claim 1 , wherein the first conducting component comprises a first nanoparticle. 
     
     
         7 . The electrochemical cell of  claim 6 , wherein the second conducting component comprises a second nanoparticle. 
     
     
         8 . The electrochemical cell of  claim 1 , wherein the second conducting component comprises a first nanoparticle. 
     
     
         9 . The electrochemical cell of  claim 1 , wherein the first conducting component comprises a material is selected from the group consisting of platinum (Pt), iridium (Ir), ruthenium (Ru), palladium (Pd), rhodium (Rh), osmium (Os), nickel (Ni), cobalt (Co), iron (Fe), copper (Cu), and their combinations. 
     
     
         10 . The electrochemical cell of  claim 1 , wherein the electrochemical cell is configured to adsorb CO2 onto the cathode and adsorb the hydrocarbon onto the anode in response to applying a voltage between the cathode exposed to a first fluid comprising CO2 and the anode exposed to a second fluid comprising the hydrocarbon. 
     
     
         11 . The electrochemical cell of  claim 10 , wherein the voltage is sufficient to simultaneously oxidize the hydrocarbon to a first olefin and reduce the CO 2  to form a second olefin. 
     
     
         12 . The electrochemical cell of  claim 11 , wherein the oxidation of the hydrocarbon is configured to occur via a dehydrogenation reaction.