Articles, devices, systems, and methods for solar energy storage and/or utilization

Abstract

The present invention generally relates to articles, devices, systems, and methods relating to the storage of solar energy and/or solar energy utilization. In some embodiments, the articles, devices, and systems may be used to carry out photocatalytic reactions, for example, the photocatalytic production of oxygen and/or hydrogen gases from water.

1 . An article for carrying out an photochemical oxidation and/or reduction reaction at the surface of water, the article comprising:
 a first anode;   a first cathode; and   a first photoactive material, wherein at least a portion of the first photoactive material is in electrical communication with the first anode and the first cathode,   wherein the article has a density less than or equal to the density of water such that at least a portion of the article, when placed in water, is above the surface of the water.   
     
     
         2 . The article of  claim 1 , wherein the first cathode is not in physical contact with the first anode. 
     
     
         3 . The article of  claim 1 , further comprising a core material. 
     
     
         4 . The article of  claim 3 , wherein the first anode, the first cathode, the first photoactive material, and the core are integrally connected. 
     
     
         5 . The article of  claim 1 , further comprising:
 a second anode;   a second cathode, wherein the second cathode is not in physical contact with the second anode; and   a second photoactive material, wherein at least a portion of the second photoactive material is in contact with the second anode and the second cathode,   wherein the second anode is in contact with the first cathode and the second cathode is not in contact with the first anode, or alternatively, wherein the second cathode is in contact with the first anode and the second anode is not in contact with the first cathode.   
     
     
         6 . A device, comprising:
 a first anode and a first cathode, wherein the first cathode is not in physical contact with the first anode;   a first photoactive material section, wherein at least a portion of the first photoactive material section is in contact with the first anode and the first cathode;   a second anode and a second cathode, wherein the second cathode is not in physical contact with the second anode; and   a second photoactive material section, wherein at least a portion of the second photoactive material section is in contact with the second anode and the second cathode,   wherein the second anode is in contact with the first cathode and the second cathode is not in contact with the first anode, or alternatively, wherein the second cathode is in contact with the first anode and the second anode is not in contact with the first cathode.   
     
     
         7 . A method of forming oxygen and hydrogen gases from water, comprising:
 providing a device, comprising:   a first anode and a first cathode, wherein the first cathode is not in physical contact with the first anode;   a first photoactive material section, wherein at least a portion of the first photoactive material section is in contact with the first anode and the first cathode;   a second anode and a second cathode, wherein the second cathode is not in physical contact with the second anode; and   a second photoactive material section, wherein at least a portion of the second photoactive material section is in contact with the second anode and the second cathode,   wherein the second anode is in contact with the first cathode and the second cathode is not in contact with the first anode, or alternatively, wherein the second cathode is in contact with the first anode and the second anode is not in contact with the first cathode, and   wherein the device does not comprise an external power source; and   exposing the device to electromagnetic radiation thereby forming oxygen gas at the at least one anode and hydrogen gas at the at least one cathode.   
     
     
         8 . The article of  claim 1 , wherein the first anode is associated with an anodic catalytic material. 
     
     
         9 . The article of  claim 1 , wherein the second cathode is associated with a cathodic catalytic material. 
     
     
         10 . The article of  claim 1 , further comprising at least one stabilizing fin. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . The article of  claim 1 , wherein at least a portion of the article is encapsulated with an encapsulant material. 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . The article of  claim 5 , further comprising:
 a third anode;   a third cathode, wherein the third cathode is not in physical contact with the third anode; and   a third photoactive material section, wherein at least a portion of the third photoactive material section is in contact with the third anode and the third cathode,   wherein the third cathode is in contact with the second cathode and the third cathode is not in contact with the first anode or the second anode, or alternatively, wherein the third cathode is in contact with the second anode and the third anode is not in contact with the first cathode or the second cathode.   
     
     
         17 . (canceled) 
     
     
         18 . The article of  claim 1 , wherein the first anode is in direct electrical communication with the first photoactive material and/or the first cathode is in direct electrical communication with the first photoactive material. 
     
     
         19 . The article or a method of  claim 1 , wherein the first anode is in indirect electrical communication with the first photoactive material and/or the first cathode is in indirect electrical communication with the first photoactive material. 
     
     
         20 . The article of  claim 5 , wherein the second anode is in direct electrical communication with the second photoactive material and/or the second cathode is in direct electrical communication with the second photoactive material. 
     
     
         21 . The article of  claim 5 , wherein the second anode is in indirect electrical communication with the second photoactive material and/or the second cathode is in indirect electrical communication with the second photoactive material. 
     
     
         22 . The article of  claim 5 , wherein at least one anode is capable of carrying out an oxidation reaction and/or at least one cathode is capable of carrying out a reduction reaction. 
     
     
         23 . The article of  claim 1 , wherein the article has an average cross section area of at least about 10 nm, about 20 nm, about 50 nm, about 100 nm, about 200 nm, about 500 nm, about 1 μm, about 5 μm, about 10 μm, about 50 μm, about 100 μm, about 500 μm, about 1 mm, about 5 mm, about 1 cm, about 2 cm, about 5 cm, about 10 cm, about 50 cm, or about 100 cm. 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . The device of  claim 6 , wherein the device has a density less than or equal to the density of water such that at least a portion of the device, when placed in water, is above the surface of the water. 
     
     
         27 . (canceled) 
     
     
         28 . A system comprising a plurality of articles as in  claim 1 . 
     
     
         29 . (canceled)