Maghemite/reduced graphene oxide nanocomposite has been successfully deposited onto the surface of a gold-coated D-shaped optical fiber. The synergetic combination of gold, graphene, and iron oxide nanoparticles has shown enhancement of the resonance field and sensitivity of the fiber-based plasmonic sensor. In particular, the sensor exhibited its capability to detect lead ions (Pb²⁺) in aqueous solution via monitoring the spectral response of the sensor probe to different concentrations of Pb²⁺. A sensor sensitivity of 1.2 nm per μg/L was attained at the lowest detected Pb²⁺ concentration, which is 0.001 ppm (limit of detection). This robust, compact, and highly sensitive fiber-based plasmonic sensor will be of a great interest for an in situ and real-time water safety environmental monitoring.

中文翻译：

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基于纤维的表面等离子体共振传感器，用于水溶液中铅离子的检测

磁赤铁矿/还原石墨烯氧化物纳米复合材料已成功沉积到镀金D形光纤的表面上。金，石墨烯和氧化铁纳米颗粒的协同组合已显示出基于纤维的等离子体传感器的共振场和灵敏度得到了增强。特别地，该传感器表现出其通过监测传感器探针对不同浓度的Pb ²⁺的光谱响应来检测水溶液中铅离子（Pb ²⁺）的能力。在检测到的最低Pb ²⁺浓度下，传感器灵敏度为1.2 nm /μg/ L浓度为0.001 ppm（检测极限）。这种坚固，紧凑且高度灵敏的基于光纤的等离子体传感器对于现场和实时水安全环境监测将具有极大的兴趣。