Development of modern societies and survival of human beings depend on the way we can master sustainable sources of energy. Hydrogen is an excellent energy carrier and zero-emission fuel, but it is mainly generated by methods relying on fossil fuels. Our project focuses on photoelectrochemical systems, where hydrogen is generated at interface between organic solvent and water. Organic solvent will contain molecules of electron donors, and generate hydrogen at water-organic solvent interface in the presence of sunlight, and are regenerated at the electrode. Organic solvent droplets will be deposited on the electrode surface or will be suspended in water to collide with the electrode. In other approach emulsion will be pumped through a photoelectrochemical cell. We will constructed and investigated new biphasic systems that may generate hydrogen with high efficiency. Fundamental knowledge on photoelectrochemical systems generating hydrogen will be also gathered.