Modified electrodes and methods of making

Abstract

Some aspects of the present disclosure are generally directed to systems for electrochemically generating compounds, for example, for generating hydrogen peroxide or other applications. In some cases, the systems may include electrodes containing a substrate comprising non-woven fibers comprising carbon, PTFE particles on the substrate, and/or an active material, for example, carbon particles, on the substrate and/or the PTFE. In some embodiments, the systems may generate and/or flow a two-phase solution over and/or through at least a portion of an electrode. Some systems using the electrode structures and/or two-phase solution may promote the formation of three-phase boundaries, and thus may facilitate the electrocatalytic generation of certain compounds at the three-phase boundaries. Still other aspects are directed to methods of making and/or using the systems, or the like.

1 . A method of modifying an electrode, comprising:
 providing the electrode comprising a non-woven substrate including fibers comprising carbon;   pretreating the electrode by applying a first solution comprising a liquid having a vapor pressure of greater than or equal to 1 kPa and a first hydrophobic polymer to the electrode; and   applying a second solution comprising a second hydrophobic polymer and/or PTFE binder and an active material comprising carbon to the electrode.   
     
     
         2 . The method of  claim 1 , wherein the liquid in the first solution comprises an organic solvent. 
     
     
         3 . The method of  claim 1 , wherein the liquid in the first solution comprises a polar organic solvent. 
     
     
         4 . The method of  claim 1 , wherein the liquid in the first solution comprises an alcohol. 
     
     
         5 . The method of  claim 1 , wherein the liquid in the first solution comprises isopropyl alcohol. 
     
     
         6 . The method of  claim 1 , wherein the second solution comprises water. 
     
     
         7 . The method of  claim 1 , wherein the second solution comprises a surfactant. 
     
     
         8 . The method of  claim 1 , wherein the non-woven substrate comprises a carbon felt. 
     
     
         9 . The method of  claim 1 , further comprising heating the electrode. 
     
     
         10 . The method of  claim 9 , wherein heating the electrode occurs in an atmosphere having a temperature of greater than or equal to 380° C. 
     
     
         11 . The method of  claim 9 , wherein heating the electrode occurs in a non-oxidative atmosphere. 
     
     
         12 . The method of  claim 9 , wherein the non-oxidative atmosphere contains less than or equal to 1 wt % oxygen. 
     
     
         13 . The method of  claim 9 , wherein heating the electrode occurs in an atmosphere comprising N 2  and/or Ar. 
     
     
         14 . The method of  claim 1 , further comprising repeating the step of pretreating the electrode. 
     
     
         15 . The method of  claim 1 , wherein the liquid in the first solution has a vapor pressure of less than or equal to 30 kPa. 
     
     
         16 . The method of  claim 1 , wherein the first hydrophobic polymer comprises polytetrafluoroethylene (PTFE) particles. 
     
     
         17 . The method of  claim 16 , wherein the second hydrophobic polymer comprises polytetrafluoroethylene (PTFE) particles. 
     
     
         18 . The method of  claim 17 , wherein the polytetrafluoroethylene (PTFE) particles of the first and/or second hydrophobic polymer are from a PTFE powder and/or micropowder.