Efficient colorful perovskite solar cells designed by 2D and 3D ordered titania inverse opals

Abstract Improving light-harvesting conversion efficiency (η) is a major step towards commercializing perovskite solar cells (PSCs). Inverse opals prepared from TiO2 show enhanced light absorption, and improved efficiency, due to increased light scattering. Besides improving efficiency, the cells are colorful and aesthetically pleasing for use in practical applications. In this study, three-dimensional (3D) highly-porous inverse opals were fabricated for use in PSCs. The light-harvesting efficiency (LHE%) and the photovoltaic performance of these colorful ordered structures were studied for the first time. Moreover, two different architectures are presented by integrating a mesoporous TiO2 (mp-TiO2) layer with an optically active two-dimensional TiO2 film. Herein, we report the highest known power conversion efficiency for bilayer TiO2/PSCs compared to standard mesoporous TiO2 films. The data indicate improved incident photon to current conversion efficiency values due to enhanced quantum efficiency in the red range of the electromagnetic spectrum. Other approaches relating to the characteristics of optical properties and photovoltaic performances of different geometries of PSCs are discussed.