Organohalide Lead Perovskites: More Stable than Glass under Gamma‐Ray Radiation

Abstract

high-throughput fabrication of perovskite modules has also been demon strated with simple processes such as blade coating with module efficiency close to 15%. [8] It remains unclear as to whether the perovskite solar cells can operate over 25 years in a real-world environment that is filled with oxygen and moisture, which are their two major stressors. Enhanced encapsulation has clearly shown to elongate the operational lifetime of perovskite solar cells to a much longer duration, indicating that the intrinsic stability of perovskite solar cells may be much longer than expected. [9][10][11] Nevertheless, perovskite solar cells may find their niche applications in space where oxygen or moisture does not exist. For space applications, there are new stressors such as radiation that may impose new threats to the stability of perovskite solar cells, while stability of solar cells under radiation has been rarely studied. The increasing interest in perovskite-based X-ray and gamma-ray detectors warrants an imperative study of the stability of perovskite materials and devices under ionizing radiation. [12,13] Less than a handful of studies have been performed to reveal the effects of proton, electron, and X-ray irradiation on perovskite so far. [14][15][16][17] Miyazawa et al. irradiated perovskite solar cells with 1 MeV electrons and found that the devices retained 93% of their peak performance after irradiation with a fluence of 1 × 10 16 cm −2 . [15] Experiments conducted by Lang et. al. [14] indicated a decrease in short-circuit current density (J SC ) by 20% for perovskite solar cells exposed to a proton dose of 1 × 10 13 p cm −2 . The perovskite self-healed with recovery on fill factor (FF) and open-circuit voltage (V OC ) after the proton irradiation terminated. [16] The effects of soft X-ray exposure on uncovered perovskites were investigated by Motoki et al. who reported that soft X-ray irradiation resulted in the evaporation of perovskite surface with residual elements in the form of crystalline PbI 2 . Apart from above stability studies with different radiation sources, the stability of perovskite device under gamma-ray radiation is also important but remained virtually unexplored. [18] Large amounts of gamma-rays are inevitably produced when the galactic cosmic rays, comprising mainly protons and alpha particles, undergo nuclear interactions with the constituent nuclei of the spacecraft, which poses a challenge to the perovskite materials for their long-term application in space. Moreover, organohalide perovskites also showed great Organohalide metal perovskites have emerged as promising semiconductor materials for use as space solar cells and radiation detectors. However, there is a lack of study of their stability under operational conditions. Here a stability study of perovskite solar cells under gamma-rays and visible light simultaneously is reported. The perovskite active layers are shown to retain 96.8% of their initial power conversion efficiency under continuous irradiation of gamma-rays and light for...

Detection of X‐Rays by Solution‐Processed Cesium‐Containing Mixed Triple Cation Perovskite Thin Films

“…Indeed, the combination of thin films and long carrier diffusion length allows in perovskites the efficient collection of photogenerated charges, even in the presence of defects or radiation‐induced traps, resulting in a higher radiation tolerance than thicker films and single crystals. Also, Yang et al demonstrated the excellent radiation hardness of hybrid perovskite thin layers under gamma‐ray irradiation. Such studies confirm the actual interest on perovskite solar cells and X‐ray detectors based on thin films for space application, where lightweight, large area, mechanical flexibility, and radiation hardness are crucial features as, e.g., in satellite missions.…”

Recent Advances in Lead Halide Perovskites for Radiation Detectors

“…Except for testing the performance of perovskite‐based γ‐ray detectors, Yang et. al . studied the operation stability of the hybrid perovskite Cs 0.05 FA 0.81 MA 0.14 PbI 2.55 Br 0.45 under hard γ‐rays.…”

Perovskites for Laser and Detector Applications

“…For a standard halide perovskite like CsPbI 3, the a value is 14 cm À1 which is larger than cadmium zinc tellurides (CZT) materials. [48] In contrast, the performance of CZT detectors drop significantly after exposure to 30 kGv c-irradiation. [47] In medical applications, the number of X-ray doses given to a subject to probe into a target organ should be minimized given the patient's health condition.…”

“…Reproduced with permission. [48] Copyright 2019, Wiley-VCH typically contain heavy atoms, are well suited to detect high energy radiations like X-ray or c-ray radiations. This is because perovskite detectors benefit from their large absorption coefficient for high energy radiation with good photoconduction properties and can be solution processed for industrial upscaling.…”

“…The PCE of a standard LHP cell was reported to stay constant up to 1500 h upon exposure to c-ray as shown in Figure 3. [48] In contrast, the performance of CZT detectors drop significantly after exposure to 30 kGv c-irradiation. [49] In 2017, Shrestha and co-workers [50] demonstrated a sintering method to develop 200 µm to 1 nm thick MAPbI 3 wafers.…”