Integration of Photonic Crystals into Flexible Dye Solar Cells: A Route toward Bendable and Adaptable Optoelectronic Devices Displaying Structural Color and Enhanced Efficiency

Abstract

Herein is presented what is believed to be the fi rst example of integration of photonic structures in a fl exible optoelectronic device. The resulting devices may be designed to display any color in the visible range and, simultaneously, present enhanced power conversion effi ciency as a consequence of the increased light harvesting caused by the colored back refl ection. The achievement results from the incorporation of nanoparticle-based multilayers with photonic crystal properties that are modifi ed to be compatible with the chemical and physical processing of fl exible nanocrystalline titania electrodes of dye solar cells. The photovoltaic performance of these colored fl exible cells remains unaltered after one hundred bending cycles, thus showing the high-mechanical stability of the ensemble. These devices reunite most characteristics required for building integration or for the construction of solar window panes, such as light weight, stability upon bending, adaptability, and color. This work may trigger promising applications of these highly adaptable and versatile photonic crystals in other fl exible devices