Abstract:
This work has applied metal-organic frameworks (MOFs) with high adsorbability and catalytic activity to develop electrochemical sensors to determine free chlorine (free-Cl) concentrations in aqueous media. A zeolitic imidazolate frameworks, Zn(Hmim)2 (ZIF-8) has been synthesized and incorporated with CuO nanosheets to decorate a glassy carbon electrode (GCE) and provide a new sensor for free-Cl determination. The as-prepared ZIF-8 and CuO-ZIF-8 composites have been characterized by FESEM, EDX, XRD, and FT-IR analyses. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) utilized to characterize the CuO-ZIF-8/GC modified electrode electrochemically, demonstrated the ability of the sensor to measure free-Cl concentration. Using differential pulse voltammetry (DPV) and under the optimal conditions, the prepared CuO-ZIF-8/GC modified electrode showed a linear response in the 0.25-60 ppm range with a 12 ppb detection limit (LOD) for free-Cl concentration. Finally, the fabricated sensor was applied to analyze free-Cl from actual swimming pool water samples with promising 97.5 to 103.0% recoveries.
摘要:
这项工作已应用具有高吸附性和催化活性的金属有机骨架(MOFs)来开发电化学传感器,以确定水性介质中的游离氯(free-Cl)浓度。沸石咪唑酯骨架,已经合成了Zn(Hmim)2(ZIF-8),并将其与CuO纳米片结合以装饰玻碳电极(GCE),并为测定游离Cl提供了一种新的传感器。用FESEM对制备的ZIF-8和CuO-ZIF-8复合材料进行了表征,EDX,XRD,和FT-IR分析。循环伏安法(CV)和电化学阻抗谱(EIS)用于电化学表征CuO-ZIF-8/GC修饰电极,证明了传感器测量游离Cl浓度的能力。使用差分脉冲伏安法(DPV)并在最佳条件下,制备的CuO-ZIF-8/GC修饰电极在0.25-60ppm范围内显示线性响应,对游离Cl浓度的检测限(LOD)为12ppb。最后,制造的传感器用于分析实际游泳池水样品中的游离Cl,有希望的回收率为97.5%至103.0%。