Environmental performance of dye-sensitized solar cells based on natural dyes

Abstract

Dye-sensitized solar cells (DSSCs) are promising alternatives to silicon-based solar cells due to their compatibility with flexible substrates and their ability to work under low-light conditions. The performance of these solar cells mainly depends on the sensitizer structure. Sensitizers based on synthetic dyes typically exhibit the best conversion efficiency; however, they have many problems such as scarcity of metals, lengthy purification steps, high synthesis costs, and high environmental impact. Natural dyes extracted from plants have been proposed as alternatives due to their nontoxicity, facile preparation, and low production cost, although they have lower efficiencies. This study used a life cycle assessment (LCA) metohodology to investigate the environmental performances of DSSCs based on natural sensitizers. We fabricated three DSSCs based on natural dyes, obtained from the juice, pomace, and leaves of black chokeberries, and another with synthetic N719 sensitizer. The results showed that the photovoltaic module containing synthetic N719 dye had the lowest environmental impact among all analyzed impact categories. Among the modules containing natural dyes, cells with chokeberry juice dyes had the highest environmental performance.