Purple power leaves the window open

Abstract

Solar Cells Certain tunable coatings can render windows “smart” by modulating the amount of heat and light passing through them, depending on the desired temperature indoors. Powering these windows with photovoltaics seems sensible, but it is inefficient for the power source to absorb the same light that the coating is meant to regulate. Davy et al. resolve this conundrum by preparing a class of solar cells that absorb at the boundary between violet and ultraviolet. Composed from hexabenzocoronene organic semiconductors, these cells interfaced effectively with electrochromic window coatings on square-centimeter scales, leaving the rest of the optical and near-infrared regime open for modulation. Nat. Energy 2 , 17104 (2017).