Integrated membrane solar fuel production assembly

Abstract

A solar fuel production assembly comprises a separation structure including an ion conducting membrane structurally integrated with one or more solar fuel production units that absorb solar energy to drive one or more redox reactions. A reduction half-reaction occurs on a first side of the separation structure to produce one or more reduction products and an associated oxidation half-reaction occurs on an opposite second side of the separation structure to produce one or more oxidation products. The one or more reduction products are collectable from the first side and the one or more oxidation products are collectable from the second side of the separation structure. The ion conducting membrane provides facile transport of ions to reduce ion transfer ohmic losses associated with the one or more redox reactions, and also provides for separation of the one or more reduction products from the one or more oxidation products.

1 . A solar fuel production assembly, comprising:
 a separation structure including one or more ion-conducting membranes structurally integrated with one or more solar fuel production units;   wherein the one or more solar fuel production units absorb solar energy to drive one or more redox reactions, with a reduction half-reaction occurring on a first side of the separation structure to produce one or more reduction products associated with the reduction half-reaction and an associated oxidation half-reaction occurring on a second side of the separation structure opposite from the first side to produce one or more oxidation products associated with the associated oxidation half-reaction,   wherein the one or more reduction products are collectable from the first side and the one or more oxidation products are collectable from the second side, and   wherein the one or more ion-conducting membranes provides facile transport of ions to reduce ion transfer ohmic losses associated with the one or more redox reactions, and also provides for separation of the one or more reduction products from the one or more oxidation products.   
     
     
         2 . An assembly according to  claim 1 , wherein the separation structure comprises a perforated solar fuel production unit having holes, wherein each hole is covered or filled by one of the one or more ion-conducting membranes. 
     
     
         3 . An assembly according to  claim 2 , wherein the solar fuel production unit is perforated using at least one of: a chemical etching process, a vapor etching process, or a mechanical perforation process. 
     
     
         4 . An assembly according to  claim 1 , wherein the separation structure comprises a perforated ion-conducting membrane having one or more separated solar fuel production units embedded into respective perforations of the perforated ion-conducting membrane. 
     
     
         5 . An assembly according to  claim 1 , wherein the one or more solar fuel production units includes a multi-junction photosynthetically active heterostructure comprising:
 a continuous sheet-like material forming or supporting a protective structure having a plurality of cavities defining electrically insulating partitions;   a plurality of independent light absorbing units, each including one or more types or regions of n-type or p-type semiconductor material, with each independent light absorbing unit being disposed entirely within one of the plurality of cavities of the protective structure such that the protective structure partially covers and protects the semiconductor material of each independent light absorbing unit from corrosion and such that each independent light absorbing unit is separated from and independent of other light absorbing units of the multi-junction photosynthetically active heterostructure;   one or more cathodes coupled to the independent light absorbing units; and   one or more anodes coupled to the independent light absorbing units and being isolated from the one or more cathodes so that each independent light absorbing unit is autonomous from other light absorbing units.   
     
     
         6 . An assembly according to  claim 1 , wherein the one or more solar fuel production units comprise a thin film monolithic or multi-junction tandem solar cell coated with protective coating to prevent chemical and electrochemical corrosion and capped with oxidation and reduction electrocatalyst. 
     
     
         7 . An assembly according to  claim 1 , wherein each of the one or more ion-conducting membranes is an anion exchange membrane or a cation exchange membrane. 
     
     
         8 . A method for generation of fuel using solar power, the method comprising:
 providing or receiving a solar fuel production assembly comprising;
 a separation structure including one or more ion-conducting membranes structurally integrated with one or more solar fuel production units; 
 wherein the one or more solar fuel production units absorb solar energy to drive one or more redox reactions, with a reduction half-reaction occurring on a first side of the separation structure to produce one or more reduction products associated with the reduction half-reaction and an associated oxidation half-reaction occurring on a second side of the separation structure opposite from the first side to produce one or more oxidation products associated with the associated oxidation half-reaction, 
 wherein the one or more reduction products are collectable from the first side and the one or more oxidation products are collectable from the second side, and 
 wherein the one or more ion-conducting membranes provides facile transport of ions to reduce ion transfer ohmic losses associated with the one or more redox reactions, and also provides for separation of the one or more reduction products from the one or more oxidation products; 
   providing an electrolyte to the first side and the second side of the separation structure;   submitting the solar fuel production assembly to solar radiation to enable the solar radiation to drive the one or more redox reactions to generate the one or more reduction reaction products and the one or more oxidation reaction products; and   collecting at least one of the one or more reduction reaction products and the one or more oxidation reaction products.   
     
     
         9 . A method according to  claim 8 , wherein the electrolyte comprises water. 
     
     
         10 . A method according to  claim 8 , wherein the electrolyte comprises at least one of: wastewater, seawater, and brine water. 
     
     
         11 . A method according to  claim 8 , wherein the one or more redox reactions comprise water electrolysis, wherein the one or more reduction products comprise hydrogen gas, and the one or more oxidation products comprise oxygen gas. 
     
     
         12 . A method according to  claim 8 , wherein the separation structure comprises a perforated solar fuel production unit having holes, wherein each hole is covered or filled by one of the one or more ion-conducting membranes. 
     
     
         13 . A method according to  claim 12 , wherein the solar fuel production unit is perforated using at least one of: a chemical etching process, a vapor etching process, or a mechanical perforation process. 
     
     
         14 . A method according to  claim 8 , wherein the separation structure comprises a perforated ion-conducting membrane having one or more separated solar fuel production units embedded into respective perforations of the perforated ion-conducting membrane. 
     
     
         15 . A method according to  claim 8 , wherein the one or more solar fuel production units includes a multi-junction photosynthetically active heterostructure comprising:
 a continuous sheet-like material forming or supporting a protective structure having a plurality of cavities defining electrically insulating partitions;   a plurality of independent light absorbing units, each including one or more types or regions of n-type or p-type semiconductor material, with each independent light absorbing unit being disposed entirely within one of the plurality of cavities of the protective structure such that the protective structure partially covers and protects the semiconductor material of each independent light absorbing unit from corrosion and such that each independent light absorbing unit is separated from and independent of other light absorbing units of the multi-junction photosynthetically active heterostructure;   one or more cathodes coupled to the independent light absorbing units;   one or more anodes coupled to the independent light absorbing units and being isolated from the one or more cathodes so that each independent light absorbing unit is autonomous from other light absorbing units;   wherein each anode and cathode is capped with an oxidation and reduction electrocatalyst; and   a hydrogen permeable layer covering the one or more cathodes.   
     
     
         16 . A method according to  claim 8 , wherein the one or more solar fuel production units comprise a thin film monolithic or multi-junction tandem solar cell coated with protective coating to prevent chemical and electrochemical corrosion and capped with oxidation and reduction electrocatalyst. 
     
     
         17 . (canceled) 
     
     
         18 . An assembly according to  claim 4 , wherein at least one of the separated solar fuel production units is perforated and has at least one hole, the at least one hole being covered or filled by an ion-conducting membrane. 
     
     
         19 . An assembly according to  claim 5 , wherein each anode and cathode is capped with an oxidation and reduction electrocatalyst. 
     
     
         20 . An assembly according to  claim 5 , further comprising a hydrogen permeable layer covering the one or more cathodes. 
     
     
         21 . A method according to  claim 14 , wherein at least one of the separated solar fuel production units is perforated and has at least one hole, the at least one hole being covered or filled by an ion-conducting membrane.