Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, PL-30059 Krakow, Poland.
Molecules. 2023 May 24;28(11):4313. doi: 10.3390/molecules28114313.
This paper presents new paste ion-selective electrodes for the determination of nitrate ions in soil. The pastes used in the construction of the electrodes are based on carbon black doped with transition metal oxides: ruthenium, iridium, and polymer-poly(3-octylthiophene-2,5-diyl). The proposed pastes were electrically characterized by chronopotentiometry and broadly characterized potentiometrically. The tests showed that the metal admixtures used increased the electric capacitance of the pastes to 470 μF for the ruthenium-doped paste. The polymer additive used positively affects the stability of the electrode response. All tested electrodes were characterized by a sensitivity close to that of the Nernst equation. In addition, the proposed electrodes have a measurement range of 10 to 10 M NO ions. They are impervious to light conditions and pH changes in the range of 2-10. The utility of the electrodes presented in this work was demonstrated during measurements directly in soil samples. The electrodes presented in this paper show satisfactory metrological parameters and can be successfully used for determinations in real samples.
本文提出了用于测定土壤中硝酸盐离子的新型糊式离子选择性电极。用于构建电极的糊剂基于掺杂有过渡金属氧化物的炭黑:钌、铱和聚合物-聚(3-辛基噻吩-2,5-二基)。所提出的糊剂通过计时电位法进行了电特性表征,并进行了广泛的电位特性表征。测试表明,所使用的金属添加剂将糊剂的电容量增加到 470 μF,对于钌掺杂的糊剂。所使用的聚合物添加剂对电极响应的稳定性有积极影响。所有测试的电极都表现出接近能斯特方程的灵敏度。此外,所提出的电极的测量范围为 10 到 10 M 的 NO 离子。它们不受光条件和 pH 值在 2-10 范围内变化的影响。本文提出的电极在直接在土壤样品中的测量中表现出良好的计量学参数,可成功用于实际样品的测定。