The detection of Fe ions is critical to environmental monitoring and disease diagnosis. We herein report fluorescent conjugated polymers that exhibit fluorescence quenching upon the addition of Fe (III) ions with the total concentration of 2 ppm. The polymer backbone consists of poly(phenylene ethynylene) (PPE) with side-chains bearing triethylene glycols or alkyl groups. The quenching phenomenon was analyzed by the Stern-Volmer equation, and the resulting Stern-Volmer constants show that the alkyl functional PPE presents higher sensitivity than the triethylene glycol functional PPE, which was unexpected. The polymer sensors showed the selectivity in that the Stern-Volmer constants for Fe³⁺ are 2–3 times higher than those for Na⁺, K⁺, and Ca²⁺. Time-resolved photoluminescence spectroscopy revealed that the quenching is static, indicating that there may be coordination between Fe (III) and alkyne/phenyl groups in the PPE backbone. For practical applications, we produced a PPE-containing, fluorescent polydimethylsiloxane (PDMS) pad. Dropping Fe solution like an ink on the pad exhibits a dark stain, demonstrating the scheme of producing Fe-detecting flexible pads for future applications in wearable sensor technology.

Fe离子的检测对于环境监测和疾病诊断至关重要。我们在本文中报道了荧光共轭聚合物，该聚合物在添加总浓度为2 ppm的Fe（III）离子后表现出荧光猝灭作用。聚合物主链由带有带有三乙二醇或烷基的侧链的聚苯撑乙炔（PPE）组成。通过Stern-Volmer方程分析了淬灭现象，所得的Stern-Volmer常数表明，烷基官能的PPE的灵敏度高于三乙二醇官能的PPE，这是出乎意料的。聚合物传感器显示出选择性，因为Fe ³⁺的Stern-Volmer常数比Na ⁺，K ⁺和Ca ²⁺的Stern-Volmer常数高2-3倍。。时间分辨的光致发光光谱表明，猝灭是静态的，表明PPE主链中的Fe（III）与炔烃/苯基之间可能存在配位作用。对于实际应用，我们生产了包含PPE的荧光聚二甲基硅氧烷（PDMS）垫。将Fe溶液像墨水一样滴在垫上会显示出深色斑点，这说明了为可穿戴传感器技术的未来应用生产检测Fe的柔性垫的方案。