The First Record of Diurnal Performance Evolution of Perovskite Solar Cells in Near Space

Abstract Perovskite solar cells (PSCs), have exhibited potential value for revolutionizing photovoltaic technology for space applications, and they have passed a series of tests in a simulated space environment. Nevertheless, the simulated space environment on land is definitely distinguished from the real‐space conditions, and the results cannot completely represent the real operating state of PSCs in space. Herein, PSCs mounted on a high‐altitude balloon are launched into near‐space and the current–voltage characteristics are measured in situ throughout the 19‐h flight, during which the PSCs are exposed directly to near‐space and experience wide temperature variation, vacuum, and strong irradiation. Thus, the diurnal performance evolution of PSCs is obtained for the first time and a possible variation mechanism is identified. The PSCs present expected stability and a champion power density of ≈12 mW cm −2 at noon, which is demonstrated as the highest result achieved in near‐space for PSCs. Additionally, despite a complex degradation process, the PSCs still deliver a high energy density comparable to that of silicon solar cells. Finally, the challenges facing the space application of PSCs are discussed. This work highlights the feasibility of PSCs in near space and provides direction for further exploration.