Fluorogenic Thorium Sensors Based on 2,6‐Pyridinedicarboxylic Acid‐Substituted Tetraphenylethenes with Aggregation‐Induced Emission Characteristics

Abstract A novel fluorescent sensor based on tetraphenylethene (TPE) modified with 2,6‐pyridinedicarboxylic acid (PDA) that shows aggregation‐induced emission (AIE) characteristics for thorium recognition with remarkable fluoresence enhancement response has been synthesized. This sensor is capable of visually distinguishing Th 4+ among lanthanides, transition metals, and alkali metals under UV light. Th 4+ can be detected by the naked eye at ppb levels owing to the AIE phenomenon. The sensor showed high selectivity for Th 4+ compared to all other metals tested, and this recognition displayed good anti‐interference qualities. This study represents the first application of a AIE fluorescence sensor in actinide metal recognition and it has potential applications in environmental systems for thorium ion detection.