A device for performing electrolysis of water is disclosed. The device may include a semiconductor structure with a surface and an electron guiding layer below said surface, the electron guiding layer of the semiconductor structure being configured to guide electron movement in a plane parallel to the surface. The electron guiding layer of the semiconductor structure may include an InGaN quantum well or a heterojunction, the heterojunction being a junction between AlN material and GaN material or between AlGaN material and GaN material and at least one metal cathode arranged on the surface of the semiconductor structure. The device may further include at least one photoanode arranged on the surface of the semiconductor structure, wherein the at least one photoanode may include a plurality of quantum dots of In.sub.xGa.sub.(1-x)N material, wherein 0.4≤x≤1. A system including such a device is also disclosed.

A device for performing electrolysis of water is disclosed. The device may include a semiconductor structure with a surface and an electron guiding layer below said surface, the electron guiding layer of the semiconductor structure being configured to guide electron movement in a plane parallel to the surface. The electron guiding layer of the semiconductor structure may include an InGaN quantum well or a heterojunction, the heterojunction being a junction between AlN material and GaN material or between AlGaN material and GaN material and at least one metal cathode arranged on the surface of the semiconductor structure. The device may further include at least one photoanode arranged on the surface of the semiconductor structure, wherein the at least one photoanode may include a plurality of quantum dots of In.sub.xGa.sub.(1-x)N material, wherein 0.4≤x≤1. A system including such a device is also disclosed.

A CaTiO.sub.3—TiO.sub.2 composite electrode and method of making is described. The composite electrode comprises a substrate with an average 2-12 μm thick layer of CaTiO.sub.3—TiO.sub.2 composite particles having average diameters of 0.2-2.2 μm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a calcium complex, and a titanium complex. The CaTiO.sub.3—TiO.sub.2 composite electrode is capable of being used in a photoelectrochemical cell for water splitting.

A CaTiO.sub.3—TiO.sub.2 composite electrode and method of making is described. The composite electrode comprises a substrate with an average 2-12 μm thick layer of CaTiO.sub.3—TiO.sub.2 composite particles having average diameters of 0.2-2.2 μm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a calcium complex, and a titanium complex. The CaTiO.sub.3—TiO.sub.2 composite electrode is capable of being used in a photoelectrochemical cell for water splitting.

The present disclosure relates to a carbon dioxide capture device comprising a first reactor and a second reactor both of which show a (photo)anode containing or connected to oxygen evolution and/or carbon dioxide evolution catalyst(s) and a (photo)cathode containing or connected to an oxygen reduction catalyst, wherein the first reactor comprises an anion exchange membrane placed between the porous (photo)anode and porous (photo)cathode, and the second reactor comprises a proton exchange membrane placed between the porous (photo)anode and porous (photo)cathode. On the porous (photo)cathode side of the first reactor there is a fluid inlet able to carry carbon dioxide, air and water, and on the side of the porous (photo)cathode of the second reactor there is a fluid outlet able to carry carbon dioxide and water.

A photoelectrochemical cell includes a cathode with a front and back cathode surface, an anode with front and back anode surfaces, a conductive connector between the cathode and the anode, and an optical waveguide configured to direct sunlight to the back surfaces of the cathode and anode. The cathode is adapted for photoelectric generation of electrons at the back cathode surface and electrolytic generation of hydrogen at the front cathode surface. Similarly, the anode is adapted for photoelectric generation of electrons at the back anode surface and electrolytic generation of oxygen at the front anode surface. The photoelectrochemical cell may also include a waveguide optical concentrator coupled to the waveguide.

A photoelectrochemical cell includes a cathode with a front and back cathode surface, an anode with front and back anode surfaces, a conductive connector between the cathode and the anode, and an optical waveguide configured to direct sunlight to the back surfaces of the cathode and anode. The cathode is adapted for photoelectric generation of electrons at the back cathode surface and electrolytic generation of hydrogen at the front cathode surface. Similarly, the anode is adapted for photoelectric generation of electrons at the back anode surface and electrolytic generation of oxygen at the front anode surface. The photoelectrochemical cell may also include a waveguide optical concentrator coupled to the waveguide.

Provided is a photocathode structure including: a photocathode including silicon (Si); an intermediate layer formed on the photocathode, and including a silicon oxide (SiO.sub.x); and a protective layer foiled on the intermediate layer, and including a metal oxide, wherein the intermediate layer is a tunneling barrier configured to transfer charges from the photocathode to the protective layer by an electric field applied from an outside.

Provided is a photocathode structure including: a photocathode including silicon (Si); an intermediate layer formed on the photocathode, and including a silicon oxide (SiO.sub.x); and a protective layer foiled on the intermediate layer, and including a metal oxide, wherein the intermediate layer is a tunneling barrier configured to transfer charges from the photocathode to the protective layer by an electric field applied from an outside.

A gas-phase reduction device for carbon dioxide includes: an oxidation chamber containing an oxidation electrode; a reduction chamber to which carbon dioxide is supplied; a gas reduction sheet that has an ion exchange membrane and a reduction electrode laminated together therein and that is disposed between the oxidation chamber and the reduction chamber with the ion exchange membrane facing the oxidation chamber and the reduction electrode facing the reduction chamber; a conducting wire that connects the oxidation electrode and the reduction electrode; and a heat source that surrounds the reduction chamber.