Abstract: A monolithic catalyst system for the cleavage of water into hydrogen and oxygen comprises a first photoactive material capable by itself or together with an auxiliary material and/or an auxiliary catalyst when irradiated with light having a wavelength?420 nm of generating oxygen and protons from water, and a second photoactive material capable by itself or together with an auxiliary material and/or an auxiliary catalyst when irradiated with light having a wavelength?420 nm of reducing protons in water to hydrogen. The first and second photoactive materials are in electrical contact via an electron-conducting material.

Abstract: A monolithic catalyst system for the cleavage of water into hydrogen and oxygen with the aid of light comprises a first photoactive material capable by itself or together with one or more of an auxiliary material and an auxiliary catalyst of generating oxygen and protons from water, when irradiated with light having a wavelength ?420 nm of generating oxygen and protons from water, and a second photoactive material selected from gallium arsenide, copper indium disulphide/selenide, copper indium gallium disulphide/selenide and cadmium sulphide/selenide/telluride and having a water resistant coating transparent to visible light capable of the reducing protons in water to hydrogen, when irradiated with visible light. The first photoactive material and the second photoactive material are supported on at least one substrate and are in electrical contact, particularly in direct electrical contact, exclusively via one or more electron-conducting materials.

Abstract: Described is a monolithic catalyst system (1) for the cleavage of water into hydrogen and oxygen with the aid of light, comprising a first photoactive material (50) capable by itself or together with one or more auxiliary catalysts when irradiated with light having a wavelength ?420 nm of generating oxygen and protons from water, and a second photoactive material (60) capable by itself or together one or more auxiliary catalysts (92) when irradiated with light having a wavelength ?420 nm of reducing protons in water to hydrogen, the first photoactive material (50) and second photoactive material (60) being in electrical contact via one or more electron-conducting materials (30, 20, 40, 60a) the system being in that characterized in that a load or an electric consumer is interposed in between at least one electron-conducting material. Likewise described is a method of generating oxygen, hydrogen and electricity from water using the catalyst system.