A light-driven fuel cell includes a cathode, an anode, and a proton-permeable membrane between the anode and the cathode. The anode includes a photocatalyst for anaerobic methane oxidation reaction, and when the anode is supplied with methane and water and is irradiated with light, methanol, protons and electrons are generated by anaerobic methane oxidation reaction from the methane and the water supplied to the anode; the protons pass through the proton-permeable membrane and move to the cathode; and the electrons move to the cathode via an external circuit. The cathode includes a photocatalyst for aerobic methane oxidation reaction, and when the cathode is supplied with methane and oxygen and is irradiated with light, methanol and water are generated by aerobic methane oxidation reaction from the methane and the oxygen supplied to the cathode and the protons and the electrons moved from the anode.

A light-driven fuel cell includes a cathode, an anode, and a proton-permeable membrane between the anode and the cathode. The anode includes a photocatalyst for anaerobic methane oxidation reaction, and when the anode is supplied with methane and water and is irradiated with light, methanol, protons and electrons are generated by anaerobic methane oxidation reaction from the methane and the water supplied to the anode; the protons pass through the proton-permeable membrane and move to the cathode; and the electrons move to the cathode via an external circuit. The cathode includes a photocatalyst for aerobic methane oxidation reaction, and when the cathode is supplied with methane and oxygen and is irradiated with light, methanol and water are generated by aerobic methane oxidation reaction from the methane and the oxygen supplied to the cathode and the protons and the electrons moved from the anode.

A device for hydrogen separation has a tank holding water. A membrane is attached to an open top of the tank. A portion of the membrane is immersed in the water of the tank and outer edges of the membrane are attached to the tank and above the water. A pair of electrodes is coupled to the outer edges of the membrane. A light source is positioned above the water, wherein the light excites the water on top of the membrane causing H.sub.2 to be released.

A device for hydrogen separation has a tank holding water. A membrane is attached to an open top of the tank. A portion of the membrane is immersed in the water of the tank and outer edges of the membrane are attached to the tank and above the water. A pair of electrodes is coupled to the outer edges of the membrane. A light source is positioned above the water, wherein the light excites the water on top of the membrane causing H.sub.2 to be released.

A method for forming an ordered array of one-dimensional iron oxide nanostructures involves forming an electrode on a template and forming a plurality of one-dimensional iron nanostructures in the template. A portion of the template is at least partially removed to expose a portion of each of the plurality of one-dimensional iron nanostructures. The plurality of one-dimensional iron nanostructures are annealed while the portion of each of the plurality of one-dimensional iron nanostructures is exposed to form an ordered array of iron-oxide one-dimensional nanostructures. The at least partial removal of the portion of the template involves complete removal of the template or a partial removal so that top portion of each of the plurality of one-dimensional iron nanostructures is exposed and a bottom portion of each of the plurality of one-dimensional iron nanostructures is within the template during annealing.

A method for forming an ordered array of one-dimensional iron oxide nanostructures involves forming an electrode on a template and forming a plurality of one-dimensional iron nanostructures in the template. A portion of the template is at least partially removed to expose a portion of each of the plurality of one-dimensional iron nanostructures. The plurality of one-dimensional iron nanostructures are annealed while the portion of each of the plurality of one-dimensional iron nanostructures is exposed to form an ordered array of iron-oxide one-dimensional nanostructures. The at least partial removal of the portion of the template involves complete removal of the template or a partial removal so that top portion of each of the plurality of one-dimensional iron nanostructures is exposed and a bottom portion of each of the plurality of one-dimensional iron nanostructures is within the template during annealing.

A radiation-assisted (typically solar-assisted) electrolyzer cell and panel for high-efficiency hydrogen production comprises a photoelectrode and electrode pair, with said photoelectrode comprising either a photoanode electrically coupled to a cathode shared with an anode, or a photocathode electrically coupled to an anode shared with a cathode; electrolyte; gas separators; all within a container divided into two chambers by said shared cathode or shared anode, and at least a portion of which is transparent to the electromagnetic radiation required by said photoanode (or photocathode) to apply photovoltage to a shared cathode (or anode) that increases the electrolysis current and hydrogen production.

A radiation-assisted (typically solar-assisted) electrolyzer cell and panel for high-efficiency hydrogen production comprises a photoelectrode and electrode pair, with said photoelectrode comprising either a photoanode electrically coupled to a cathode shared with an anode, or a photocathode electrically coupled to an anode shared with a cathode; electrolyte; gas separators; all within a container divided into two chambers by said shared cathode or shared anode, and at least a portion of which is transparent to the electromagnetic radiation required by said photoanode (or photocathode) to apply photovoltage to a shared cathode (or anode) that increases the electrolysis current and hydrogen production.

To enhance water electrolysis efficiency by supporting a catalyst on an oxide carrier at a high density. A catalyst layer includes a carrier and a catalyst. The carrier is a nanosheet made of an oxide containing at least one element selected from Ti, Mn, Co, Mo, Ru, W, Nb, and Ta. The catalyst is supported on the carrier.

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.