Molecular Ordering in Low‐Dimensional Hybrid Perovskites for Improved X‐Ray Detection

Abstract Low‐dimensional hybrid perovskites are emerging semiconductors with excellent photophysical property, chemical stability, and structural diversity and have shown prominence in the fields of solar cells, light‐emitting diodes, and X‐ray detectors. To date, the inorganic framework structure in perovskites has been intensively studied, but the molecular arrangement of organic counterparts and its impact on physical properties remains largely unexplored. Herein, we engineer the coordination geometry of inorganic and organic building units to implement molecular ordering and π–π stacking in low‐dimensional perovskites. We observe a positive dependence of carrier transport capacity and environmental stability on the molecular regularity in hybrid perovskites. Furthermore, 5‐aminoquinoline lead iodide single crystal with the highest regularity exhibit nearly 5‐fold increased carrier mobility‐lifetime product and 20‐fold decreased ionic conductivity along [011] than [100] orientation, enabling a high sensitivity of 8.25 × 10 5 µC Gy air −1 cm −2 under 8 keV X‐ray radiation for radiation detection application. This work sheds light on the design and synthesis of next‐generation perovskite‐based semiconductors with enhanced performance and stability for optoelectronic applications.