Photo-catalytic systems for the production of hydrogen
AssigneeSunpower Technologies LLC
InventorDANIEL LANDRY
Life of this patent
Estimating the term…
Abstract
A system and method for splitting water to produce hydrogen and oxygen employing sunlight energy are disclosed. Hydrogen and oxygen may then be stored for later use as fuels. The system and method use inorganic capping agents that cap the surface of semiconductor nanocrystals to form photocatalytic capped colloidal nanocrystals, which may be deposited on a substrate and treated to form a photoactive material. The photoactive material may be employed in the system to harvest sunlight and produce energy necessary for water splitting. The system may also include elements necessary to collect, transfer and store hydrogen and oxygen, for subsequent transformation into electrical energy.
Claims29
A method for producing photocatalytic capped colloidal nanocrystals, comprising
- reacting a semiconductor nanocrystals precursor and an organic solvent to produce organic capped semiconductor nanocrystals;
- substituting an inorganic capping agent for the organic capping agent, including
- dissolving the inorganic capping agent in a first solvent to produce a first solution;
- dissolving the organic capped nanocrystals in a second solvent to produce a second solution;
- combining the first solution and the second solution in a single vessel;
- reacting the first solution with the second solution, whereby a portion of the organic capping agent is displaced by inorganic capping agent;
- continuing reacting until the combination reaches equilibrium;
- allowing the combination to stabilize;
- and
- precipitating photocatalytic capped colloidal nanocrystals from the combination.
A photocatalytic capped colloidal nanocrystal, comprising
- a first semiconductor nanocrystal;
- a first inorganic capping agent overlying at least a first face of the nanocrystal;
- a second inorganic capping agent overlying at least a second face of the nanocrystal.
A method for splitting water molecules, comprising
- submerging a photoactive material in water contained in a reaction vessel;
- and
- inducing reduction-oxidation reactions in the water, including
- illuminating the photoactive material with the incident light, the incident light including photons having an energy level greater than the band gap of the photoactive material;
- exciting electrons in the photoactive material from the valence band into the conduction band, as a result of the illuminating;
- forming holes in the photoactive material as a result of the exciting;
- reducing water molecules to form hydrogen gas as a result of the exciting electrons;
- and
- oxidizing water molecules to form oxygen gas as a result of the forming.
Dependencies are inferred from the claim text.