PRIN RESELECT

In the context of the so-called Energetic Transition, Europe has embarked on a difficult challenge, applying to become the first climate-neutral continent in the world by 2050. This fact could be strongly compromised by the current situation, in which many EU countries are deciding to return to the use of coal for energy production, which will obviously lead to an increase in CO₂ emissions. In this context, driving the restart towards more environmentally sustainable models, helping countries to minimize the energy dependence on others, becomes fundamental. In this historical moment the exploitation of renewable energies takes on an even greater role, and the green hydrogen represents a key link for the sustainability and functionality of future decarbonised energy systems. Among the different processes for the green hydrogen production, electrochemical water splitting remains the most reliable and efficient technology: high purity H₂ can be originated by this environmentally benign process, so that, differently from the conventionally used reforming processes, the hydrogen obtained may be directly used without energy consuming purification treatments. However, high costs due to the need of noble metal catalysts and membrane separator still make H₂ production from water electrolysis not competitive with grey H₂ from fossil fuels. The photo electrochemical (PEC) cell proposed by RESELECT could give a contribute solving this problem. A membraneless PEC cell is planned in which the cost of both structure and operative process will be lowered. Optimization of the fluid-dynamics of the cell, as well as the suitable geometry of the electrodes will allow the separation of the anodic and cathodic reaction products, originated at the porous structures irradiated by solar light. The aim of the project will be to produce high purity H₂ with minimum power supply. The main challenges will be: i) to optimize the design of the cell body, in such a way that crossover between anodic and cathodic flows can be avoided; ii) to reduce the needed power supply by planning the coupling of the electrodes in such a way that at least one of them is photo-active at high wavelength of incident light, so that the efficiency of the process will be maximized.