Hybrid organic–inorganic lead halide perovskites (HOIPs) possess significant photoelectric characteristics for solar energy conversion, but the presence of lead causes issues for eco-friendly applications. Halide double perovskites represent a green option for application in the optoelectronic field, especially X-ray detection systems. Despite the great efforts, the exploration of large-size lead-free iodide-based hybrid double perovskite single crystals for X-ray detection has been unsuccessful. Herein, we demonstrate that a large single crystal of the 2D (two-dimensional) semiconducting perovskite (C₆H₁₆N₂)₂CuBiI₈·0.5H₂O can serve as an X-ray detection candidate. A perovskite crystal, as large as 35 × 31 × 3 mm³, was grown using a low-cost, simple cooling solution approach. To the best of our knowledge, this is the first time a centimeter-sized 2D BiCu iodide double perovskite single crystal has been used for X-ray detection. The perovskite crystal exhibited unique properties for X-ray detection, such as a significant X-ray absorption coefficient, considerable μτ product, and low trap density. Moreover, X-ray detection with a sensitivity of 5.51 μC Gy_air⁻¹ cm⁻² was achieved based on a single crystal. This work opens new ways to explore specially designed organic cations for stabilizing 2D HOIPs that show great potential in optoelectronics.

中文翻译：

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厘米大小的无铅碘化物基杂化双钙钛矿单晶可实现高效的 X 射线光响应性

混合有机-无机卤化铅钙钛矿（HOIPs）在太阳能转换方面具有显着的光电特性，但铅的存在会给环保应用带来问题。卤化物双钙钛矿代表了在光电领域应用的一种绿色选择，尤其是 X 射线检测系统。尽管付出了巨大的努力，但用于 X 射线探测的大尺寸无铅碘基杂化双钙钛矿单晶的探索并未成功。在此，我们证明了二维（二维）半导体钙钛矿（C ₆ H ₁₆ N ₂）₂ CuBiI ₈ ·0.5H _{2的大单晶}O可以作为X射线检测候选。使用低成本、简单的冷却溶液方法生长了35 × 31 × 3 mm ^{3的钙钛矿晶体。}据我们所知，这是第一次将厘米大小的 2D BiCu 碘化物双钙钛矿单晶用于 X 射线检测。钙钛矿晶体在 X 射线探测方面表现出独特的特性，例如显着的 X 射线吸收系数、相当大的μτ积和低陷阱密度。此外，X 射线检测灵敏度为 5.51 μC Gy _air ^-1 cm ^-2是基于单晶实现的。这项工作开辟了探索特殊设计的有机阳离子的新方法，用于稳定在光电子学中显示出巨大潜力的 2D HOIP。