An ultra-highly sensitive and selective self-enhanced AIECL sensor for public security early warning in a nuclear emergency via a co-reactive group poisoning mechanism

Abstract

The worldwide application of nuclear power has created the potential risk of a nuclear accident, which has been a challenge to public security. In nuclear leakages, I₂ radioisotopes would cause rapid, global pollution. Therefore, highly sensitive and selective I₂ sensors exhibit their significance in nuclear accident early warnings and treatments. Herein, a conjugated polymer was developed for I₂ vapor monitoring with an ultra-low limit of detection (LOD). This polymer, modified with a tertiary amine as a co-reactive group, exhibits aggregation-induced electrochemiluminescence (AIECL) and self-enhanced ECL behaviors. It is noteworthy that the tertiary amine also acts as I₂ vapor capturing and sensing groups to give a LOD of 0.13 ppt. Excellent selectivity was obtained in various interfering atmospheres. A new mechanism was discovered for designing vapor sensors, which is summarized as co-reactive group poisoning (CGP). To meet the high efficiency requirement of nuclear emergency monitoring, an I₂ sensor modified screen printed carbon electrode was used due to its low cost, lack of need for pretreatment and suitability for mass production. A matching upwardly photosensitive ECL dark box was further designed. This study reports ECL vapor monitoring for the first time and provides a novel strategy for early warning of a nuclear emergency, suggesting its significance in environmental and public security fields.