Advances on Dye-Sensitized Solar Cells (DSSCs) Nanostructures and Natural Colorants: A Review

Abstract

Human beings are attempting to take advantage of renewable natural resources by using solar cells. These devices take the sun’s radiation and convert it into electrical energy. The issue with traditional silicon-based solar cells is their manufacturing costs and environmental problems. For this reason, alternatives have been developed within the solar cell field. One of these alternatives is the dye-sensitized solar cell (DSSC), also known as Grätzel solar cells. DSSCs are a type of solar cell that mimics photosynthesis. They have a photoanode, which is formed by a semiconductor film sensitized with a dye. Some of their advantages include low-cost manufacturing, eco-friendly materials use, and suitability for most environments. This review discusses four important aspects, with two related to the dye, which can be natural or synthetic. Herein, only natural dyes and their extraction methods were selected. On the other hand, this paper discusses the nanostructures used for DSSCs, the TiO2 nanostructure being the most reported; it recently reached an efficiency level of 10.3%. Finally, a review on the novelties in DSSCs technology is presented, where it is observed that the use of Catrin protein (cow brain) shows 1.45% of efficiency, which is significantly lower if compared to Ag nanoparticles doped with graphene that report 9.9% efficiency.