The current work deals with fabrication and validation of a new highly Fe3+ selective sensor based on benzo-18-crown-6 (b-18C6) using the potentiometric method. The proposed sensor revealed satisfactory performance for quantitative evaluation of Fe3+ trace amount in environmental samples. The ratio of membrane ingredients optimized and the membrane with the composition of 4:30:65.5:0.5 mg of b-18C6:PVC:o-NPOE:KTpClPB exhibited the desirable Nernstian slope of 19.51 ± 0.10 (mV per decade of activity) over the pH range from 2.5 to 5.7 with an acceptable dynamic concentration range of 1.0 × 10-6 M to 1.0 × 10-1 M and lower detection limit of 8.0 × 10-7 M. The proposed sensor demonstrated an appropriate reproducibility with a rapid response time of 12 s and the suitable lifetime of 10 weeks. To validate the accurate response of the proposed sensor, AAS technique applied for the determination of Fe3+ in real aqueous mediums such as drinking tap water and hospital wastewater sample after treatment by electrocoagulation process. Theoretical studies carried out using DFT/B3LYP computational level with 6-311G basis set to optimize the adsorption sites of Fe+3 cationic species by b-18C6. The obtained adsorption energy with large negative value confirmed the formation of a stable complex.

中文翻译：

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铁（III）定量测定的电位传感器：实验和计算方法。

当前的工作涉及使用电位计方法基于苯并18冠6（b-18C6）的新型高Fe3 +选择性传感器的制造和验证。拟议中的传感器显示出令人满意的性能，用于定量评估环境样品中的痕量Fe3 +。优化的膜成分比例和b-18C6：PVC：o-NPOE：KTpClPB组成为4：30：65.5：0.5 mg的膜在整个过程中表现出理想的能斯登斜率（19.51±0.10）（mV /十活性年） pH范围为2.5至5.7，可接受的动态浓度范围为1.0×10-6 M至1.0×10-1 M，检测下限为8.0×10-7M。所提出的传感器具有良好的重现性，并具有快速响应时间为12秒，适用寿命为10周。为了验证所建​​议传感器的准确响应，原子吸收光谱法用于电凝法处理后的真实水性介质（如饮用水，自来水和医院废水样品）中的三价铁的测定。使用DFT / B3LYP计算水平和6-311G基础进行的理论研究，以优化b-18C6对Fe + 3阳离子物质的吸附位。所获得的具有大负值的吸附能证实形成稳定的配合物。