Photoinduced polymerization: An innovative, powerful and environmentally friendly technique for the preparation of polymer electrolytes for dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) have attracted large attention due to their easy fabrication, low cost and high conversion efficiency. One of the major problems limiting the long-term stability of these devices is the volatilization of the liquid electrolytes traditionally used. To solve this problem and improve technological perspectives of DSSCs, many recent studies have been addressed to the preparation of quasi-solid electrolytes, in which a polymer network is able to effectively retain the redox mediator and its additives. In this context, photoinduced polymerization is increasingly proving to be the most effective method of preparation of these polymer electrolytes, since it is a rapid, economic, functional and environmentally friendly process, besides being easily transferable to the industrial scale. This review focuses on the techniques adopted for the preparation of UV-cured quasi-solid electrolytes, on the expedients designed to overcome the inhibition phenomena typical of some photoinitiated mechanisms, and on the evaluation of photoelectric performance obtained in presence of these photopolymer electrolytes.