A water based and metal free dye solar cell exceeding 7% efficiency using a cationic poly(3,4 ethylenedioxythiophene) derivative+
A green, efficient and stable solar cell based only on water and safe and cheap elements of the periodic table is proposed in this work, finally consolidating (also from a sustainability viewpoint) the concept of "artificial photosynthesis" studied for decades by the scientific community. The concept of dye sensitized solar cells is re proposed here with a metal free organic dye, an iodine based electrolyte in a 100% aqueous environment and a new cathode (cationic PEDOT) synthesized for the first time with the aim of inhibiting the repulsion between the anions of redox couples and the PEDOT:PSS matrix commonly used as the counter electrode. This elegant setup leads to a record efficiency of 7.02% the highest value ever obtained for a water based solar cell and, in general, for a photovoltaic device free of both organic solvents and expensive/heavy metals.
Chemical science