Exploring centimeter-sized single crystals of a 2D Dion–Jacobson halide perovskite toward efficient X-ray detection†

Two-dimensional (2D) halide hybrid perovskites have become feasible semiconductors for high-performance X-ray detection due to their strong radiation-blocking ability, high volume resistivity, and large mobility-lifetime (μτ) product. However, the absence of large-high-quality single crystals (SCs) and excessive operating voltages make it still challenging to manufacture perovskite X-ray devices with stable dark current, low detection limit, and high sensitivity. Here, utilizing (S)-1-(4-nitrophenyl)ethanamine hydrochloride cations, a centimeter-sized 2D Dion–Jacobson (DJ) alide perovskite [(S)-1-(4-aminophenyl)ethylamine]PbI₄ (1) is synthesized, and an X-ray detector with high-performance is constructed. Specifically, the 1 SC device has a large volume resistivity of 6.01 × 10¹⁰ Ω cm, resulting in a low and stable dark current (25.03 pA) and noise current (0.32 pA) of the X-ray device. Consequently, the detection limit is as low as 236 nGy_air s⁻¹ at a 5 V bias. Additionally, the SC device of 1 exhibits a μτ product up to 6.21 × 10⁻⁴ cm² V⁻¹, which brings a detection sensitivity of 270 μC Gy_air⁻¹ cm⁻² at a 5 V bias. Moreover, the sensitivity is further improved to 1410 μC Gy_air⁻¹ cm⁻² at a 10 V bias. Notably, 1 exhibits outstanding environmental stability and radiation resistance. Its excellent detection performance renders it a viable option for low-dose X-ray detection.