We report a Ni2+ heavy metal sensor based on a graphene oxide (GO) functionalized micro-tapered long-period fiber grating (MTLPG) where light–matter interaction is enhanced. With high-quality GO coating on fiber with strong adhesion and controllable thickness, the GO-coated MTLPG demonstrated a resonant wavelength shift and intensity change, corresponding to a sensitivity of up to 5.12 × 10−4 nm ppb−1 and 3.07 × 10–4 dB ppb−1, respectively. Moreover, the limits of detection were 2.5 ppb and 0.27 ppb, respectively, operating in a wider concentration range of 1 ppb to 1 × 107 ppb. The proposed optical platform can be developed for superior chemical sensing applications.

中文翻译：

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用于敏感重金属传感的氧化石墨烯功能化微锥形长周期光纤光栅

我们报告了一种基于氧化石墨烯 (GO) 功能化微锥形长周期光纤光栅 (MTLPG) 的 Ni2+ 重金属传感器，其中光-物质相互作用增强。GO 涂层的高品质 GO 涂层附着力强且厚度可控，GO 涂层 MTLPG 表现出共振波长偏移和强度变化，对应的灵敏度高达 5.12 × 10−4 nm ppb−1 和 3.07 × 10–分别为 4 dB ppb-1。此外，检测限分别为 2.5 ppb 和 0.27 ppb，在 1 ppb 至 1 × 107 ppb 的更宽浓度范围内运行。所提议的光学平台可以开发用于卓越的化学传感应用。