Artificial photosynthesis systems and methods for producing carbon-based chemical compounds

Patent metadata

Field	Value
Publication number	US-2016264920-A1
Application number	US-201615061378-A
Country	US
Kind code	A1
Filing date	Mar 4, 2016
Priority date	Mar 11, 2015
Publication date	Sep 15, 2016
Grant date	—

Abstract

This disclosure provides systems, methods, and apparatus related to artificial photosynthesis. In one aspect a system includes a photoanode chamber including a photoanode assembly, a photocathode chamber including a photocathode assembly, an electrical connection electrically connecting the photoanode assembly and the photocathode assembly, a membrane separating the photoanode chamber and the photocathode chamber, and a microorganism disposed in the photocathode chamber. The photoanode assembly is operable to oxidize water to generate oxygen, protons, and electrons. The membrane is permeable to the protons and operable to allow the protons to travel to the photocathode chamber. The electrical connection provides electrons to the photocathode assembly. The microorganism comprises a metabolic pathway to reduce carbon dioxide and to generate a carbon-based compound using the electrons or hydrogen formed by two protons.

First claim

What is claimed is:

1 . A system comprising:
a photoanode chamber including a photoanode assembly, the photoanode assembly comprising a first plurality of nanostructures disposed on a first substrate; a photocathode chamber including a photocathode assembly, the photocathode assembly comprising a second plurality of nanostructures disposed on a second substrate; an electrical connection electrically connecting the photoanode assembly and the photocathode assembly; a membrane separating the photoanode chamber and the photocathode chamber, the photoanode assembly operable to oxidize water to generate oxygen, protons, and electrons, the membrane being permeable to the protons and operable to allow the protons to travel to the photocathode chamber, the electrical connection operable to provide electrons to the photocathode assembly; and a microorganism disposed in the photocathode chamber, the microorganism comprising a metabolic pathway to reduce carbon dioxide and to generate a carbon-based compound using the electrons or hydrogen formed by two protons.

2 . The system of claim 1 , wherein the first plurality of nanostructures comprises titanium oxide, wherein the second plurality of nanostructures comprises silicon, wherein the microorganism comprises Sporomsa ovata, and wherein the carbon-based compound comprises acetate.

3 . The system of claim 1 , wherein the first plurality of nanostructures comprises titanium oxide, wherein the second substrate plurality of nanostructures comprises indium phosphide, wherein the microorganism comprises Methansarcina barkeri, and wherein the carbon-based compound comprises methane.

4 . The system of claim 1 , wherein the microorganism is selected from a group consisting of bacteria and archaea.

5 . The system of claim 1 , wherein the microorganism comprises an archaea belonging to the genus Methansarcina.

6 . The system of claim 1 , wherein the microorganism comprises a bacteria belonging to the genus Sporomsa.

7 . The system of claim 1 , wherein the microorganism is disposed on the second plurality of nanostructures of the photocathode assembly.

8 . The system of claim 1 , wherein the photoanode assembly, the photocathode assembly, the membrane, and the microorganism are disposed in water when the system is in operation, and wherein the water has about 0.5 grams/liter to 30 grams/liter of a salt dissolved in the water.

9 . The system of claim 8 , wherein the photocathode chamber includes an inlet and an outlet, wherein the inlet is operable to allow the carbon dioxide to flow though the water and be dissolved in the water, and wherein the outlet is operable to allow a portion of the carbon dioxide not dissolved in the water to flow out of the photocathode chamber.

10 . The system of claim 1 , wherein the first plurality of nanostructures comprises a plurality of nanowires, wherein the plurality of nanowires is disposed on the first substrate with an end of each of the plurality of nanowires being in contact with the first substrate, and wherein a length of each of the plurality of nanowires forms an angle with the substrate of about 45 degrees to 90 degrees.

11 . The system of claim 1 , further comprising:
an ultraviolet light (UV) filter positioned to block UV light from irradiating the photocathode assembly.

12 . The system of claim 1 , wherein the membrane is impermeable to oxygen and oxygen radicals.

13 . The system of claim 1 , wherein the photocathode assembly is coated with an oxide layer.

14 . The system of claim 1 , wherein the photocathode assembly is coated with a metal layer.

15 . The system of claim 1 , wherein the photoanode assembly comprises an n-type semiconductor, and wherein the photoanode assembly comprises a p-type semiconductor.

16 . The system of claim 15 , wherein the n-type semiconductor has a larger band gap than the p-type semiconductor.

17 . A method comprising:
providing a device comprising:
a photoanode chamber including a photoanode assembly, the photoanode assembly comprising a first plurality of nanostructures disposed on a first substrate;
a photocathode chamber including a photocathode assembly, the photocathode assembly comprising a second plurality of nanostructures disposed on a second substrate;
an electrical connection electrically connecting the photoanode assembly and the photocathode assembly;
a membrane separating the photoanode chamber and the photocathode chamber, the photoanode, the photocathode, and the membrane being disposed in water, and the membrane being impermeable to oxygen and oxygen radicals; and
a microorganism disposed in the photocathode chamber;
irradiating the photoanode assembly with a first light and irradiating the photocathode assembly with a second light, the photoanode oxidizing the water to generate oxygen, protons, and electrons, the electrons being provided to the photocathode assembly by the electrical connection, the protons travelling through the membrane to the photocathode chamber; and forming a carbon-based compound with the microorganism using the electrons or hydrogen formed by two protons.

18 . The method of claim 17 , wherein the water has about 0.5 grams/liter to 30 grams/liter of salt dissolved in the water.

19 . The method of claim 17 , wherein the first light includes more wavelengths of light than the second light.

20 . The method of claim 17 , wherein the photoanode assembly comprises an n-type semiconductor, and wherein the photoanode assembly comprises a p-type semiconductor.

Assignees

• Univ California

Inventors

• Yang Peidong
• Chang Michelle C Y
• Chang Christopher J
• Liu Chong
• Gallagher Joseph J
• Nichols Eva M

Classifications

• C12M31/00

  Means for providing, directing, scattering or concentrating light (C12M41/06 takes precedence) · CPC title

• C12M35/02 Primary

  Electrical or electromagnetic means, e.g. for electroporation or for cell fusion · CPC title

• C12M23/34

  Internal compartments or partitions · CPC title

• C12M25/02

  Membranes; Filters (filters or filtration in general B01D24/00-B01D41/00) · CPC title

• C12P5/023 Primary

  Methane · CPC title