Thermally and electrically tunable infrared perovskite devices for alternatively cooling and heat energy harvesting

Abstract

Radiative energy harvesting from the sun and outer space is a feasible pathway to develop novel low-carbon energy technologies. However, most reported radiative energy harvesting is discontinuous during the alternation of day and night. Herein, a simple intelligent device is designed for all-weather radiative energy harvesting by depositing bendable mica substrate through oxide perovskite. Under thermal excitation, the intelligent device exhibits a comparable infrared emissivity as the emissivity at the phase transition temperature of 323 K. Below the phase transition temperature, it is first reported that the infrared emissivity shows a significant electrically adjustable characteristic, which increases with the increase of voltage. Outdoor experiments demonstrate that the intelligent device can achieve a sub-ambient temperature drop of 8 °C with a harvested cooling energy of 62W/m2 at nighttime and a temperature rise of 75 °C with a harvested heat energy of 627W/m2 at daytime. More importantly, the bendable mica substrate provides good flexibility for devices, making it easy to attach to any flat or non-flat surface. This intelligent design promotes the development of bendable perovskite devices with alternating cooling and heat acquisition.