A promising research area, which could provide a solution to the high energy demands of our society, as well as to the devastating effects of greenhouse gases, has arisen from the idea of using CO2 as chemical feedstock for fuel production. The capture, conversion and storage of a sustainable, clean and secure energy represents an important multidisciplinary research area.The goal of artificial photosynthesis is to mimic the conversion of water and CO2 under solar irradiation, carried out by plants and other bacteria, to obtain high-energy chemicals for energy production. Light induced water splitting and CO2 reduction devices at a molecular level require the integration of at least three essential components in a stable supramolecular architecture: a photosensitiser, a water oxidation catalyst and a CO2 reduction catalyst. An interesting way for the incorporation of this catalytic system in a complete functional device is the so called dye sensitised photoelectrochemical cell. In this device, the oxidation and reduction reactions take place at the anode and cathode electrodes of an electrochemical cell.The aim of this proposal is the development and study of an efficient photocathode, composed of a photosensitiser, a semiconductor support and a catalyst for the reduction of CO2 into fuels. This electrode will then be integrated into a new molecular-based device able to produce high value chemicals such as CH3OH or CH4 from CO2. A clear advantage of this innovative scheme is that it allows the study of the kinetic reactions that occur at the CO2 reduction electrode and the mechanisms of the photochemical CO2 reduction in an independent system. The final device will be prepared as a composition of two different sub-systems: for water splitting and CO2 reduction. The electrodes included in the final device are exactly the same systems studied independently, therefore the kinetic studies and mechanisms of action will be applicable to the complete system.