Final Report Summary - PHOTOCATH2ODE (Gathering organic and hybrid photovoltaics with artificial photosynthesis for Photo-Electro-Chemical production of hydrogen) The future of energy supply depends on innovative breakthroughs regarding the design of efficient systems for the conversion and storage of the most available source of renewable energy, solar energy. The production of hydrogen through direct sunlight-driven water splitting in a Photo-Electro-Chemical (PEC) cell, appears as a promising and appealing solution. However such cells need to respond to three main characteristics: sustainability, cost-effectiveness and stability. Fulfilling these requirements raise important scientific questions regarding mainly the elaboration and the combination of the best possible materials able to harvest light and catalyse H2 and O2 evolution.Within this project, we have fabricated operating photocathodes based on Earth abundant elements for the conversion of solar light energy into hydrogen answering therefore the sustainability and cost-effectiveness issues. The novelty relies on the approach gathering organic photovoltaics and dye-sensitized solar cell technology with noble-metal free catalysts developed in the context of artificial photosynthesis. To select the catalyst, we developed tools to benchmark their activity for H2 evolution and to study their mode of action so that rational optimization becomes possible. We also developed a methodology at the interface between chemistry and biology to fully activate hydrogenase enzymes, the natural catalysts present in some microbes and algae to produce hydrogen.
