Colored, see-through perovskite solar cells employing an optical cavity†
Multi-functional solar cells that can create semitransparency or desired colors have recently garnered much attention due to their potential in incorporating aesthetic functionalities into building envelopes, such as windows, facades, and walls, allowing large surfaces of the buildings to be utilized for light-harvesting. Here, we present optical microcavity-embedded decorative perovskite solar cells producing distinctive transmissive colors. Any individual semitransparent colors can be created by strong interference effects in the microcavity system, which are easily tuned by changing the thickness of the optical spacer layer of the microcavity. Our colored cell devices show a power conversion efficiency of up to ∼4% with high internal quantum efficiency that is attributed to greatly minimized charge carrier recombination. This approach could bring us one step closer towards energy-saving ultra-thin color display devices and power generating panels for building decoration.