Wang Tan, Wang Cong, Xu Xianbao, Li Zhen, Li Daoliang
National Innovation Center for Digital Fishery, China Agricultural University, Beijing 100083, China.
College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China.
Nanomaterials (Basel). 2021 Jul 23;11(8):1892. doi: 10.3390/nano11081892.
In this paper, a new nanocomposite AuNPs/MXene/ERGO was prepared for sensitive electrochemical detection of nitrite. The nanocomposite was prepared by a facile one-step electrodeposition, HAuCl4, GO and MXene mixed in PBS solution with the applied potential of -1.4 V for 600 s. The modified material was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and cyclic voltammetry (CV). The electrochemical behavior of nitrite at the modified electrode was performed by CV and chronoamperometry. The AuNPs/MXene/ERGO/GCE showed a well-defined oxidation peak for nitrite at +0.83 V (Vs. Ag/AgCl) in 0.1 M phosphate buffer solution (pH 7). The amperometric responses indicated the sensor had linear ranges of 0.5 to 80 μM and 80 to 780 μM with the LOD (0.15 μM and 0.015 μM) and sensitivity (340.14 and 977.89 μA mM cm), respectively. Moreover, the fabricated sensor also showed good selectivity, repeatability, and long-term stability with satisfactory recoveries for a real sample. We also propose the work that needs to be done in the future for material improvements in the conclusion.
本文制备了一种新型纳米复合材料AuNPs/MXene/ERGO,用于亚硝酸盐的灵敏电化学检测。该纳米复合材料通过简便的一步电沉积法制备,将HAuCl4、氧化石墨烯(GO)和MXene在磷酸盐缓冲溶液(PBS)中混合,施加-1.4 V的电位600 s。采用扫描电子显微镜(SEM)、能量色散X射线光谱(EDS)、X射线衍射(XRD)和循环伏安法(CV)对改性材料进行表征。通过CV和计时电流法研究了亚硝酸盐在修饰电极上的电化学行为。在0.1 M磷酸盐缓冲溶液(pH 7)中,AuNPs/MXene/ERGO修饰的玻碳电极(GCE)在+0.83 V(相对于Ag/AgCl)处对亚硝酸盐有明确的氧化峰。安培响应表明该传感器对亚硝酸盐的线性范围分别为0.5至80 μM和80至780 μM,检测限(LOD)分别为0.15 μM和0.015 μM,灵敏度分别为340.14和977.89 μA mM cm。此外,所制备的传感器还具有良好的选择性、重复性和长期稳定性,对实际样品的回收率令人满意。在结论部分,我们还提出了未来在材料改进方面需要开展的工作。