A new all-inorganic vacancy-ordered double perovskite Cs2CrI6 for high-performance photovoltaic cells and alpha-particle detection in space environment

Although MAPbI3 photovoltaics have gained increasing interest for space application, its low stability and radiation resistance is insurmountable. Here, we unexpectedly find a new vacancy-ordered double perovskite Cs2CrI6 to realize high-performance space solar cells and α-particle detectors through an innovative multi-scale simulation strategy based on the first-principle calculations coupling with drift-diffusion model and Monte Carlo method. Compared to the MAPbI3, Cs2CrI6 possesses more excellent stability and optical absorption, suitable band gap (1.08 eV), higher mobility (∼103 cm2/V) and lower capture cross-section. These lead to the ultra-high power conversion efficiency (PCE) for single-junction solar cells (22.4%) and monolithic all-perovskite tandem solar cells (26.6%), and excellent α-particle detectors with ultra-high charge collection efficiency (CCE = 99.3%) and mobility-lifetime product (μτh = 4.99 × 10−3 cm2V−1), which are superior to those of corresponding MAPbI3 devices. Meanwhile, the 90% of initial PCE can be remained even under the 5 × 1013 p. cm−2 fluence proton beam and several orders higher than traditional space solar cell. Moreover, the proton irradiation resistance of Cs2CrI6 α-particle detection can reach up to 1016 p. cm−2. The excellent device performance and irradiation resistance of Cs2CrI6 devices indicate the great potential application in photovoltaic cells, α-particle detectors and even their space applications.