The present disclosure relates to a hydrogen evolution apparatus including an AC power source, a semiconductor electrode and a counter electrode connected to the AC power source, an electrolyte in which the semiconductor electrode is immersed, and a light source which irradiates light on the semiconductor electrode, in which the semiconductor electrode includes a conductive substrate and n-type semiconductor particles dispersed on a p-type semiconductor matrix or p-type semiconductor particles dispersed on an n-type semiconductor matrix which is vertically grown from the conductive substrate.

The present disclosure relates to a hydrogen evolution apparatus including an AC power source, a semiconductor electrode and a counter electrode connected to the AC power source, an electrolyte in which the semiconductor electrode is immersed, and a light source which irradiates light on the semiconductor electrode, in which the semiconductor electrode includes a conductive substrate and n-type semiconductor particles dispersed on a p-type semiconductor matrix or p-type semiconductor particles dispersed on an n-type semiconductor matrix which is vertically grown from the conductive substrate.

One or more novel processes for producing hydrogen, oxygen, and in some cases, distilled and cleaned water from a contaminated effluent, are disclosed. In one example of utilizing this novel process, the water from contaminated effluent is transferred into a draw solution using an entrochemical system through a vapor-mediated membrane-free forward osmosis process. The process is enabled by the generation of a wet vacuum in one or more entrochemical cells incorporated into the entrochemical system. This process generates a diluted draw solution that can be utilized as an abundant water feedstock in an electrolyzer for electrolysis, which in turn generates hydrogen and oxygen. In some embodiments, an entrochemical distiller may also be utilized to distill a portion of the contaminated effluent for clean water as a result of thermal transfers during the vapor-mediated membrane-free forward osmosis process.

An electrode for a reaction in a chemical cell includes a substrate having a surface, an array of nanostructures supported by the substrate and extending outward from the surface of the substrate, each nanostructure of the array of nanostructures having a semiconductor composition, and a catalyst arrangement disposed along each nanostructure of the array of nanostructures, the catalyst arrangement comprising a metal-based catalyst for the reaction in the chemical cell. The semiconductor composition of each nanostructure of the array of nanostructures establishes sites at which the metal-based catalyst is anchored to the nanostructure. The array of nanostructures and the catalyst arrangement are configured such that the metal-based catalyst is distributed along sidewalls of each nanostructure of the array of nanostructures at an atomic scale.

An electrode for a reaction in a chemical cell includes a substrate having a surface, an array of nanostructures supported by the substrate and extending outward from the surface of the substrate, each nanostructure of the array of nanostructures having a semiconductor composition, and a catalyst arrangement disposed along each nanostructure of the array of nanostructures, the catalyst arrangement comprising a metal-based catalyst for the reaction in the chemical cell. The semiconductor composition of each nanostructure of the array of nanostructures establishes sites at which the metal-based catalyst is anchored to the nanostructure. The array of nanostructures and the catalyst arrangement are configured such that the metal-based catalyst is distributed along sidewalls of each nanostructure of the array of nanostructures at an atomic scale.

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 bismuth vanadate electrode including vanadium-functionalized graphene quantum dots and a method for preparing the same. More particularly, it relates to a technology which is capable of, by adding graphene quantum dots (GQDs) in the process of immersing a bismuth vanadate (BiVO.sub.4) electrode in an alkaline solution to remove vanadium oxide (V.sub.2O.sub.5) excessively formed on the surface of the electrode during its preparation, protecting the electrode from the alkaline solution as the graphene quantum dots are adsorbed onto the surface of BiVO.sub.4 while V.sub.2O.sub.5 is removed, and improving the efficiency of oxygen evolution reaction (OER) when applied to a photoanode due to vanadium (V)-functionalized graphene quantum dots formed as the etched vanadium ions ((VO).sub.4.sup.3−) are adsorbed onto the graphene quantum dots.

The present invention provides a photodecomposition module and a photodecomposition cell that have a new structure different from a known art and can decompose a decomposition liquid more effectively than those of the known art. The present invention includes a plurality of photodecomposition cells, and a posture holder that holds each of the photodecomposition cells in a predetermined posture, in which each of the photodecomposition cells decomposes a decomposition liquid with light irradiation, and includes an anode electrode part and a cathode electrode part in an accommodating part, the anode electrode part has a photocatalyst supported on a conductive substrate, the anode electrode part and the cathode electrode part are immersed in the decomposition liquid in the accommodating part, and the accommodating part has a cylindrical shape.

Proposed are a photoelectrochemical cell for producing hydrogen peroxide, a method of fabricating the same, and a method of producing hydrogen peroxide using the photoelectrochemical cell. The photoelectrochemical cell includes a photoanode including a photocatalyst, a cathode, and a solid polymer electrolyte layer disposed between the photoanode and the cathode and including a solid polymer electrolyte. The photoelectrochemical cell is for use in the production of hydrogen peroxide, and can produce hydrogen peroxide with electric energy generated from solar energy without requiring the supply of external electric energy.