Abstract

Herein, a novel catechol sensor made of double-layers of functionalized multi-walled carbon nanotubes coated zinc oxide on a glassy carbon electrode (fMWCNTs/ZnO@fMWCNTs/GCE) is synthesized. The FTIR spectrum reveals that the ZnO NPs are successfully functionalized on the fMWCNT while SEM analysis shows granular colloids on the surface of ZnO@fMWCNTs nanocomposites. The XRD study confirms the crystalline nature of the ZnO peaks and the ZnO interaction with fMWCNTs structure. The fabricated sensor responds to a wide linear range of CC concentrations from 10 µM to 200 µM and sensitivity of 0.0022 µA/µM.cm² with a detection and quantification limit of 0.027 µM and 0.092 µM, respectively. Both of the limits are better than previously reported ZnO and fMWCNTs sensors. In addition, the developed fMWCNTs/ZnO@fMWCNTs/GCE demonstrates that the electron transfer is regulated by the adsorption-controlled process and can successfully detect catechol in real water samples with an excellent selectivity against hydroquinone (HQ), phenol (ph), and penta-chlorophenol (p-chph). The developed sensor exhibits satisfactory analytical performance including operational stability of 94.5%, good repeatability with a relative standard deviation (RSD) of 2.15%, and reliable reproducibility of 8 electrodes with an RSD of 3.93%.

• Research Highlights

• An antifouling double-layered functionalized multi-walled carbon nanotubes (fMWCNTs) coated zinc oxide nanoparticles (ZnO NPs) is synthesized.

• The nanocomposite (fMWCNTs/ZnO@fMWCNTs) was fabricated using a one-step in-situ adsorption method.

• In the new design of the fabricated nanocomposite, the diffusion of electrons is improved by the adsorption control mechanism.

• The developed sensor is highly sensitive and selective for sensing catechol.

• It exhibits stable and reproducible responses for practical and real analysis of catechol.

摘要

在此，合成了一种新型的儿茶酚传感器，该传感器由双层功能化多壁碳纳米管涂覆在玻璃碳电极上的氧化锌制成（f MWCNTs/ZnO@ f MWCNTs/GCE）。FTIR 光谱显示 ZnO NPs 在 f MWCNTs 上成功功能化，而SEM 分析显示 ZnO@ f MWCNTs 纳米复合材料表面上存在颗粒状胶体。XRD 研究证实了 ZnO 峰的结晶性质以及 ZnO 与f MWCNTs 结构的相互作用。制造的传感器响应从 10 µM 到 200 µM 的宽线性范围的 CC 浓度和 0.0022 µA/µM.cm ^{2的灵敏度}检测和定量限分别为 0.027 µM 和 0.092 µM。这两个限制都优于先前报道的 ZnO 和f MWCNTs 传感器。此外，开发的f MWCNTs/ZnO@ f MWCNTs/GCE 表明电子转移受吸附控制过程的调节，可以成功地检测实际水样中的儿茶酚，对氢醌 (HQ)、苯酚 (ph) 具有出色的选择性。 , 和五氯苯酚 (p-chph)。开发的传感器具有令人满意的分析性能，包括 94.5% 的操作稳定性、良好的重复性（相对标准偏差 (RSD) 为 2.15%）以及 8 个电极的可靠重现性（RSD 为 3.93%）。

• 研究亮点

• 合成了一种防污双层功能化多壁碳纳米管( f MWCNTs) 包覆的氧化锌纳米粒子 (ZnO NPs)。

• 纳米复合材料 ( f MWCNTs/ZnO@ f MWCNTs) 是使用一步原位吸附法制备的。

• 在制造的纳米复合材料的新设计中，电子的扩散通过吸附控制机制得到改善。

• 开发的传感器对检测儿茶酚具有高度的灵敏度和选择性。

• 它对儿茶酚的实际和实际分析表现出稳定和可重复的响应。