High‐Mobility 2D Molecular Crystals Enable Field‐Effect X‐Ray Detectors with Record Volumetric Sensitivity
Abstract
ABSTRACT Direct X‐ray detectors that are lightweight, low‐cost, and ultra‐sensitive are essential for next‐generation portable imaging, wearable monitoring, and low‐dose medical diagnostics. Conventional high‐performance detectors use thick single‐crystal active layers to boost sensitivity, but this increases device volume, raises dark current, and complicates integration with flexible and portable electronics. Here, we break from this paradigm with an ultrathin, high‐mobility 2D molecular crystal (2DMC) integrated into a lateral field‐effect transistor. This design employs a highly confined in‐plane carrier transport path coupled with strong gate‐electrostatic control to achieve complete carrier depletion and sub‐pA dark currents. Thanks to high‐mobility and efficient charge collection in the ultrathin channel, the detector achieves a record volumetric sensitivity of 5.91 × 10 10 µC Gy −1 cm −3 and a detection limit of 1.43 nGy s −1 , surpassing all reported organic detectors and competing with state‐of‐the‐art inorganic ones. Importantly, we show that in the ultrathin regime, high‐mobility outweighs atomic number in governing sensitivity, overturning conventional design logic. We further fabricate large‐area, uniform 2DMC arrays with excellent operational stability, enabling high‐contrast imaging at doses as low as 10.17 nGy s −1 . This work establishes a new paradigm for lightweight, low‐dose organic X‐ray imaging and introduces mobility‐centric design rules for next‐generation detectors.
Article Details
Authors (12)
Yiwen Ren
State Key Laboratory of Advanced Materials for Intelligent Sensing Key Laboratory of Organic Integrated Circuit Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of Chemistry Institute of Molecular Aggregation Science & School of Science Tianjin University Tianjin China
Hongyun Wang
State Key Laboratory of Organic–Inorganic Composites, College of Materials Science and Engineering
Yuhan Du
Miaoyu Wang
The International Joint Institute of Tianjin University Tianjin University Fuzhou China
Xianshuo Wu
Key Laboratory of Organic Integrated Circuit, Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University
Suhao Hu
State Key Laboratory of Advanced Materials for Intelligent Sensing Key Laboratory of Organic Integrated Circuit Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of Chemistry School of Science & Institute of Molecular Aggregation Science Tianjin University Tianjin P. R. China
Yidi Xie
State Key Laboratory of Advanced Materials for Intelligent Sensing Key Laboratory of Organic Integrated Circuit Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of Chemistry School of Science & Institute of Molecular Aggregation Science Tianjin University Tianjin P. R. China
Chunli Li
Hua Wang
Fangxu Yang
Key Laboratory of Organic Integrated Circuit, Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University
Lingjie Sun
State Key Laboratory of Advanced Materials for Intelligent Sensing, Key Laboratory of Organic Integrated Circuit, Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science & Institute of Molecular Aggregation Science, Tianjin University
Wenping Hu