AEE-active conjugated polymers based on di(naphthalen-2-yl)-1,2-diphenylethene for sensitive fluorescence detection of picric acid

Abstract Picric acid (PA) is an archetypal explosive material that possesses low safety coefficient and high detonation velocity. The development of reliable and effective sensors for PA using PL spectroscopy methods is practically significant. Among various PL sensors, conjugated polymers have emerged as a class of fascinating candidates for the detection of PA due to the “molecular wire” sensing mechanism. In this work, we synthesized and characterized two new di (naphthalen-2-yl)-1,2-diphenylethene (DNDPE)-based conjugated polymers with different conjugation degree and hydrophilicity. They show good solubility, aggregation-enhanced emission (AEE) feature and high photostability. Both polymers exhibit sensitive fluorescence quenching by PA, and the KSV at the initial stage of the Stern–Volmer plots is up to 9.8 × 105 M−1. In addition, after exposure to UV light, these polymers still could effectively detect the PA in water. They also could on-site detect PA with high sensitivity by preparing the polymer-immobilized fluorescent test strips. The results demonstrate that these new DNDPE-based conjugated polymeric sensors could be good candidates for the sensitive detection of PA.